Benchmark: Custom Flatmap - MeasureThat.net

HTML Preparation code:


<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.21/lodash.min.js'></script>

Script Preparation code:

const locations = [
    {'county': 'Mid Glamorgan', 'town': 'Aberdare'},
    {'county': 'Aberdeenshire', 'town': 'Aberdeen'},
    {'county': 'Gwynedd', 'town': 'Aberdovey'},
    {'county': 'Gwent', 'town': 'Abergavenny'},
    {'county': 'Clwyd', 'town': 'Abergele'},
    {'county': 'Gwent', 'town': 'Abertillery'},
    {'county': 'Dyfed', 'town': 'Aberystwyth'},
    {'county': 'Oxfordshire', 'town': 'Abingdon'},
    {'county': 'Lancashire', 'town': 'Accrington'},
    {'county': 'Lanarkshire', 'town': 'Airdrie'},
    {'county': 'Warwickshire', 'town': 'Alcester'},
    {'county': 'Suffolk', 'town': 'Aldeburgh'},
    {'county': 'Cheshire', 'town': 'Alderley Edge'},
    {'county': 'Hampshire', 'town': 'Aldershot'},
    {'county': 'Derbyshire', 'town': 'Alfreton'},
    {'county': 'Ross-shire', 'town': 'Alness'},
    {'county': 'Northumberland', 'town': 'Alnwick'},
    {'county': 'Hampshire', 'town': 'Alresford'},
    {'county': 'Cumbria', 'town': 'Alston'},
    {'county': 'Hampshire', 'town': 'Alton'},
    {'county': 'Cheshire', 'town': 'Altrincham'},
    {'county': 'Cumbria', 'town': 'Ambleside'},
    {'county': 'Buckinghamshire', 'town': 'Amersham'},
    {'county': 'Wiltshire', 'town': 'Amesbury'},
    {'county': 'Carmarthenshire', 'town': 'Ammanford'},
    {'county': 'Hampshire', 'town': 'Andover'},
    {'county': 'Fife', 'town': 'Anstruther'},
    {'county': 'Co Antrim', 'town': 'Antrim'},
    {'county': 'Cumbria', 'town': 'Appleby-in-Westmorland'},
    {'county': 'Angus', 'town': 'Arbroath'},
    {'county': 'Ayrshire', 'town': 'Ardrossan'},
    {'county': 'Co Armagh', 'town': 'Armagh'},
    {'county': 'Gwynedd', 'town': 'Arthog'},
    {'county': 'West Sussex', 'town': 'Arundel'},
    {'county': 'Berkshire', 'town': 'Ascot'},
    {'county': 'Derbyshire', 'town': 'Ashbourne'},
    {'county': 'Devon', 'town': 'Ashburton'},
    {'county': 'Kent', 'town': 'Ashford'},
    {'county': 'Middlesex', 'town': 'Ashford'},
    {'county': 'Northumberland', 'town': 'Ashington'},
    {'county': 'Surrey', 'town': 'Ashtead'},
    {'county': 'Greater Manchester', 'town': 'Ashton-under-Lyne'},
    {'county': 'Norfolk', 'town': 'Attleborough'},
    {'county': 'Inverness-shire', 'town': 'Aviemore'},
    {'county': 'Devon', 'town': 'Axminster'},
    {'county': 'Buckinghamshire', 'town': 'Aylesbury'},
    {'county': 'Ayrshire', 'town': 'Ayr'},
    {'county': 'Gwynedd', 'town': 'Bala'},
    {'county': 'Hertfordshire', 'town': 'Baldock'},
    {'county': 'Argyll', 'town': 'Ballachulish'},
    {'county': 'Co Antrim', 'town': 'Ballycastle'},
    {'county': 'Co Antrim', 'town': 'Ballyclare'},
    {'county': 'Co Antrim', 'town': 'Ballymena'},
    {'county': 'Co Antrim', 'town': 'Ballymoney'},
    {'county': 'Northumberland', 'town': 'Bamburgh'},
    {'county': 'Devon', 'town': 'Bamstaple'},
    {'county': 'Co Down', 'town': 'Banbridge'},
    {'county': 'Oxfordshire', 'town': 'Banbury'},
    {'county': 'Kincardineshire', 'town': 'Banchory'},
    {'county': 'Aberdeenshire', 'town': 'Banff'},
    {'county': 'Co Down', 'town': 'Bangor'},
    {'county': 'Gwynedd', 'town': 'Bangor'},
    {'county': 'Surrey', 'town': 'Banstead'},
    {'county': 'Essex', 'town': 'Barking'},
    {'county': 'Gwynedd', 'town': 'Barmouth'},
    {'county': 'Co Durham', 'town': 'Barnard Castle'},
    {'county': 'Hertfordshire', 'town': 'Barnet'},
    {'county': 'South Yorkshire', 'town': 'Barnsley'},
    {'county': 'Devon', 'town': 'Barnstaple'},
    {'county': 'South Glamorgan', 'town': 'Barry'},
    {'county': 'Cumbria', 'town': 'Barrow-in Furness'},
    {'county': 'South Humberside', 'town': 'Barton-upon-Humber'},
    {'county': 'Essex', 'town': 'Basildon'},
    {'county': 'Hampshire', 'town': 'Basingstoke'},
    {'county': 'Avon', 'town': 'Bath'},
    {'county': 'West Lothian', 'town': 'Bathgate'},
    {'county': 'East Sussex', 'town': 'Battle'},
    {'county': 'Gwynedd', 'town': 'Beaumaris'},
    {'county': 'Suffolk', 'town': 'Beccles'},
    {'county': 'Kent', 'town': 'Beckenham'},
    {'county': 'North Yorkshire', 'town': 'Bedale'},
    {'county': 'Bedfordshire', 'town': 'Bedford'},
    {'county': 'Belfast', 'town': 'Belfast'},
    {'county': 'Kent', 'town': 'Belvedere'},
    {'county': 'Essex', 'town': 'Benneet'},
    {'county': 'Hertfordshire', 'town': 'Berkhamsted'},
    {'county': 'Northumberland', 'town': 'Berwick-on-Tweed'},
    {'county': 'Conwy', 'town': 'Betws-y-Coed'},
    {'county': 'North Humberside', 'town': 'Beverley'},
    {'county': 'Worcestershire', 'town': 'Bewdley'},
    {'county': 'East Sussex', 'town': 'Bexhill-on-Sea'},
    {'county': 'Oxfordshire', 'town': 'Bicester'},
    {'county': 'Devon', 'town': 'Bideford'},
    {'county': 'Lanarkshire', 'town': 'Biggar'},
    {'county': 'Bedfordshire', 'town': 'Biggleswade'},
    {'county': 'Essex', 'town': 'Billericay'},
    {'county': 'West Sussex', 'town': 'Billingshurst'},
    {'county': 'West Yorkshire', 'town': 'Bingley'},
    {'county': 'Merseyside', 'town': 'Birkenhead'},
    {'county': 'West Midlands', 'town': 'Birmingham'},
    {'county': 'Co Durham', 'town': 'Bishop Auckland'},
    {'county': 'Shropshire', 'town': 'Bishops Castle'},
    {'county': 'Hertfordshire', 'town': 'Bishop\'s Stortford'},
    {'county': 'Hampshire', 'town': 'Bishops Waltham'},
    {'county': 'Lancashire', 'town': 'Blackburn'},
    {'county': 'Lancashire', 'town': 'Blackpool'},
    {'county': 'Gwynedd', 'town': 'Blaenau Ffestiniog'},
    {'county': 'Perthshire', 'town': 'Blairgowrie'},
    {'county': 'Dorset', 'town': 'Blandford Forum'},
    {'county': 'Tyne & Wear', 'town': 'Blaydon-on-Tyne'},
    {'county': 'Cornwall', 'town': 'Bodmin'},
    {'county': 'West Sussex', 'town': 'Bognor Regis'},
    {'county': 'Tyne & Wear', 'town': 'Boldon Colliery'},
    {'county': 'Lancashire', 'town': 'Bolton'},
    {'county': 'Midlothian', 'town': 'Bonnyrigg'},
    {'county': 'Merseyside', 'town': 'Bootle'},
    {'county': 'Hampshire', 'town': 'Bordon'},
    {'county': 'Hertfordshire', 'town': 'Borehamwood'},
    {'county': 'Lincolnshire', 'town': 'Boston'},
    {'county': 'West Lothian', 'town': 'Botness'},
    {'county': 'Lincolnshire', 'town': 'Bourne'},
    {'county': 'Dorset', 'town': 'Bournemouth'},
    {'county': 'Northamptonshire', 'town': 'Brackley'},
    {'county': 'Berkshire', 'town': 'Bracknell'},
    {'county': 'West Yorkshire', 'town': 'Bradford'},
    {'county': 'Essex', 'town': 'Braintree'},
    {'county': 'Cumbria', 'town': 'Brampton'},
    {'county': 'Devon', 'town': 'Braunton'},
    {'county': 'Powys', 'town': 'Brecon'},
    {'county': 'Middlesex', 'town': 'Brentford'},
    {'county': 'Essex', 'town': 'Brentwood'},
    {'county': 'Mid Glamorgan', 'town': 'Bridgend'},
    {'county': 'Shropshire', 'town': 'Bridgnorth'},
    {'county': 'Somerset', 'town': 'Bridgwater'},
    {'county': 'North Humberside', 'town': 'Bridlington'},
    {'county': 'Dorset', 'town': 'Bridport'},
    {'county': 'Lincolnshire', 'town': 'Brigg'},
    {'county': 'West Yorkshire', 'town': 'Brighouse'},
    {'county': 'East Sussex', 'town': 'Brighton'},
    {'county': 'Avon', 'town': 'Bristol'},
    {'county': 'Devon', 'town': 'Brixham'},
    {'county': 'Isle of Skye', 'town': 'Broadford'},
    {'county': 'Kent', 'town': 'Broadstairs'},
    {'county': 'Hereford & Worcester', 'town': 'Broadway'},
    {'county': 'Hampshire', 'town': 'Brockenhurst'},
    {'county': 'Isle of Arran', 'town': 'Brodick'},
    {'county': 'Kent', 'town': 'Bromley'},
    {'county': 'Hereford & Worcester', 'town': 'Bromsgrove'},
    {'county': 'Norfolk', 'town': 'Brooke'},
    {'county': 'West Lothian', 'town': 'Broxburn'},
    {'county': 'Devon', 'town': 'Buckfastleigh'},
    {'county': 'Essex', 'town': 'Buckhurst Hill'},
    {'county': 'Banffshire', 'town': 'Buckie'},
    {'county': 'Buckinghamshire', 'town': 'Buckingham'},
    {'county': 'Cornwall', 'town': 'Bude'},
    {'county': 'Devon', 'town': 'Budleigh Salterton'},
    {'county': 'Powys', 'town': 'Builth Wells'},
    {'county': 'Isle of Mull', 'town': 'Bunessan'},
    {'county': 'Suffolk', 'town': 'Bungay'},
    {'county': 'West Sussex', 'town': 'Burgess Hill'},
    {'county': 'Somerset', 'town': 'Burnham-on-Sea'},
    {'county': 'Lancashire', 'town': 'Burnley'},
    {'county': 'Staffordshire', 'town': 'Burton-on-Trent'},
    {'county': 'Lancashire', 'town': 'Bury'},
    {'county': 'Suffolk', 'town': 'Bury St Edmunds'},
    {'county': 'Co Antrim', 'town': 'Bushmills'},
    {'county': 'Derbyshire', 'town': 'Buxton'},
    {'county': 'Gwynedd', 'town': 'Caernarvon'},
    {'county': 'Mid Glamorgan', 'town': 'Caerphilly'},
    {'county': 'Wiltshire', 'town': 'Calne'},
    {'county': 'Surrey', 'town': 'Camberley'},
    {'county': 'Cambridgeshire', 'town': 'Cambridge'},
    {'county': 'Cornwall', 'town': 'Camelford'},
    {'county': 'Argyll', 'town': 'Campbeltown'},
    {'county': 'Staffordshire', 'town': 'Cannock'},
    {'county': 'Kent', 'town': 'Canterbury'},
    {'county': 'South Glamorgan', 'town': 'Cardiff'},
    {'county': 'Dyfed', 'town': 'Cardigan'},
    {'county': 'Cumbria', 'town': 'Carlisle'},
    {'county': 'Isle of Lewis', 'town': 'Carloway'},
    {'county': 'Lanarkshire', 'town': 'Carluke'},
    {'county': 'Dyfed', 'town': 'Carmarthen'},
    {'county': 'Lancashire', 'town': 'Carnforth'},
    {'county': 'Co Antrim', 'town': 'Carrickfergus'},
    {'county': 'Surrey', 'town': 'Carshalton'},
    {'county': 'Kirkcudbrightshire', 'town': 'Castle Douglas'},
    {'county': 'Co Tyrone', 'town': 'Castlederg'},
    {'county': 'Isle of Man', 'town': 'Castletown'},
    {'county': 'Co Down', 'town': 'Castlewellan'},
    {'county': 'Surrey', 'town': 'Caterham'},
    {'county': 'Gwynedd', 'town': 'Cemmaes Bay'},
    {'county': 'Gwynedd', 'town': 'Cemmaes Road'},
    {'county': 'Dorset', 'town': 'Cerne Abbas'},
    {'county': 'Somerset', 'town': 'Chard'},
    {'county': 'Kent', 'town': 'Chatham'},
    {'county': 'Cambridgeshire', 'town': 'Chatteris'},
    {'county': 'Cheshire', 'town': 'Cheadle'},
    {'county': 'Surrey', 'town': 'Cheam'},
    {'county': 'Somerset', 'town': 'Cheddar'},
    {'county': 'Essex', 'town': 'Chelmsford'},
    {'county': 'Gloucestershire', 'town': 'Cheltenham'},
    {'county': 'Gwent', 'town': 'Chepstow'},
    {'county': 'Surrey', 'town': 'Chertsey'},
    {'county': 'Buckinghamshire', 'town': 'Chesham'},
    {'county': 'Cheshire', 'town': 'Chester'},
    {'county': 'Co Durham', 'town': 'Chester-le-Street'},
    {'county': 'Derbyshire', 'town': 'Chesterfield'},
    {'county': 'West Sussex', 'town': 'Chichester'},
    {'county': 'Wiltshire', 'town': 'Chippenham'},
    {'county': 'Oxfordshire', 'town': 'Chipping Norton'},
    {'county': 'Gloucestershire', 'town': 'Chipping Sodbury'},
    {'county': 'Lancashire', 'town': 'Chorley'},
    {'county': 'Dorset', 'town': 'Christchurch'},
    {'county': 'Shropshire', 'town': 'Church Stretton'},
    {'county': 'Gloucestershne', 'town': 'Cinderford'},
    {'county': 'Gloucestershire', 'town': 'Cirencester'},
    {'county': 'Essex', 'town': 'Clacton-on-Sea'},
    {'county': 'South Humberside', 'town': 'Cleethorpes'},
    {'county': 'Avon', 'town': 'Clevedon'},
    {'county': 'Lancashire', 'town': 'Clitheroe'},
    {'county': 'Co Tyrone', 'town': 'Clogher'},
    {'county': 'Northamptonshire', 'town': 'Clopton'},
    {'county': 'Leicestershire', 'town': 'Coalville'},
    {'county': 'Lanarkshire', 'town': 'Coatbridge'},
    {'county': 'Surrey', 'town': 'Cobham'},
    {'county': 'Cumbria', 'town': 'Cockermouth'},
    {'county': 'Essex', 'town': 'Colchester'},
    {'county': 'Warwickshire', 'town': 'Coleshill'},
    {'county': 'Co Londonderry', 'town': 'Coleraine'},
    {'county': 'Clwyd', 'town': 'Colwyn Bay'},
    {'county': 'Cheshire', 'town': 'Congleton'},
    {'county': 'Cumbria', 'town': 'Coniston'},
    {'county': 'Co Durham', 'town': 'Consett'},
    {'county': 'Gwynedd', 'town': 'Conwy'},
    {'county': 'Co Tyrone', 'town': 'Cookstown'},
    {'county': 'Lancashire', 'town': 'Coppull'},
    {'county': 'Northumberland', 'town': 'Corbridge'},
    {'county': 'Northamptonshire', 'town': 'Corby'},
    {'county': 'Clwyd', 'town': 'Corwen'},
    {'county': 'Surrey', 'town': 'Coulsdon'},
    {'county': 'West Midlands', 'town': 'Coventry'},
    {'county': 'Co Armagh', 'town': 'Craigavon'},
    {'county': 'Northumberland', 'town': 'Cramlington'},
    {'county': 'Kent', 'town': 'Cranbrook'},
    {'county': 'Surrey', 'town': 'Cranleigh'},
    {'county': 'Shropshire', 'town': 'Craven Arms'},
    {'county': 'West Sussex', 'town': 'Crawley'},
    {'county': 'Devon', 'town': 'Crediton'},
    {'county': 'Cheshire', 'town': 'Crewe'},
    {'county': 'Perthshire', 'town': 'Crieff'},
    {'county': 'Norfolk', 'town': 'Cromer'},
    {'county': 'East Sussex', 'town': 'Crowborough'},
    {'county': 'Inverness-shire', 'town': 'Croy'},
    {'county': 'Surrey', 'town': 'Croydon'},
    {'county': 'Co Antrim', 'town': 'Crumlin'},
    {'county': 'Devon', 'town': 'Cullompton'},
    {'county': 'East Ayrshire', 'town': 'Cumnock'},
    {'county': 'Fife', 'town': 'Cupar'},
    {'county': 'Gwent', 'town': 'Cwmbran'},
    {'county': 'Essex', 'town': 'Dagenham'},
    {'county': 'Kirkcudbrightshire', 'town': 'Dalbeattie'},
    {'county': 'Argyll', 'town': 'Dalmally'},
    {'county': 'Ayrshire', 'town': 'Dalry'},
    {'county': 'Co Durham', 'town': 'Darlington'},
    {'county': 'Kent', 'town': 'Dartford'},
    {'county': 'Ayrshire', 'town': 'Darvel'},
    {'county': 'Northamptonshire', 'town': 'Daventry'},
    {'county': 'Kent', 'town': 'Deal'},
    {'county': 'Clwyd', 'town': 'Deeside'},
    {'county': 'Derbyshire', 'town': 'Derby'},
    {'county': 'Norfolk', 'town': 'Dereham'},
    {'county': 'Wiltshire', 'town': 'Devizes'},
    {'county': 'West Yorkshire', 'town': 'Dewsbury'},
    {'county': 'Oxfordshire', 'town': 'Didcot'},
    {'county': 'South Glamorgan', 'town': 'Dinas Powis'},
    {'county': 'Ross-shire', 'town': 'Dingwall'},
    {'county': 'Norfolk', 'town': 'Diss'},
    {'county': 'Gwynedd', 'town': 'Dolgellau'},
    {'county': 'South Yorkshire', 'town': 'Doncaster'},
    {'county': 'Dorset', 'town': 'Dorchester'},
    {'county': 'Surrey', 'town': 'Dorking'},
    {'county': 'Sutherland', 'town': 'Dornoch'},
    {'county': 'Isle of Man', 'town': 'Douglas'},
    {'county': 'Kent', 'town': 'Dover'},
    {'county': 'Norfolk', 'town': 'Downham Market'},
    {'county': 'Co Down', 'town': 'Downpatrick'},
    {'county': 'North Humberside', 'town': 'Driffield'},
    {'county': 'Hereford & Worcester', 'town': 'Droitwich'},
    {'county': 'Co Down', 'town': 'Dromore'},
    {'county': 'West Midlands', 'town': 'Dudley'},
    {'county': 'Somerset', 'town': 'Dulverton'},
    {'county': 'Dunbartonshire', 'town': 'Dumbarton'},
    {'county': 'Dumfriesshire', 'town': 'Dumfries'},
    {'county': 'East Lothian', 'town': 'Dunbar'},
    {'county': 'Perthshire', 'town': 'Dunblane'},
    {'county': 'Angus', 'town': 'Dundee'},
    {'county': 'Fife', 'town': 'Dunfermline'},
    {'county': 'Co Tyrone', 'town': 'Dungannon'},
    {'county': 'Perthshire', 'town': 'Dunkeld'},
    {'county': 'Essex', 'town': 'Dunmow'},
    {'county': 'Belfast', 'town': 'Dunmurry'},
    {'county': 'Argyll', 'town': 'Dunoon'},
    {'county': 'Berwickshire', 'town': 'Duns'},
    {'county': 'Bedfordshire', 'town': 'Dunstable'},
    {'county': 'Co Durham', 'town': 'Durham'},
    {'county': 'Gloucestershire', 'town': 'Dursley'},
    {'county': 'North Yorkshire', 'town': 'Easingwold'},
    {'county': 'West Sussex', 'town': 'East Grinstead'},
    {'county': 'South Lanarkshire', 'town': 'East Kilbride'},
    {'county': 'Surrey', 'town': 'East Molesey'},
    {'county': 'East Sussex', 'town': 'Eastbourne'},
    {'county': 'Hampshire', 'town': 'Eastleigh'},
    {'county': 'Kent', 'town': 'Ebbsfleet'},
    {'county': 'Gwent', 'town': 'Ebbw Vale'},
    {'county': 'Kent', 'town': 'Edenbridge'},
    {'county': 'Middlesex', 'town': 'Edgware'},
    {'county': 'Edinburgh', 'town': 'Edinburgh'},
    {'county': 'Surrey', 'town': 'Egham'},
    {'county': 'Morayshire', 'town': 'Elgin'},
    {'county': 'Cheshire', 'town': 'Ellesmere Port'},
    {'county': 'Aberdeenshire', 'town': 'Ellon'},
    {'county': 'Cambridgeshire', 'town': 'Ely'},
    {'county': 'Hampshire', 'town': 'Emsworth'},
    {'county': 'Middlesex', 'town': 'Enfeld'},
    {'county': 'Co Fermanagh', 'town': 'Enniskillen'},
    {'county': 'Essex', 'town': 'Epping'},
    {'county': 'Surrey', 'town': 'Epsom'},
    {'county': 'Kent', 'town': 'Erith'},
    {'county': 'Surrey', 'town': 'Esher'},
    {'county': 'Worcestershire', 'town': 'Evesham'},
    {'county': 'Devon', 'town': 'Exeter'},
    {'county': 'Devon', 'town': 'Exmouth'},
    {'county': 'Norfolk', 'town': 'Fakenham'},
    {'county': 'Stirlingshire', 'town': 'Falkirk'},
    {'county': 'Cornwall', 'town': 'Falmouth'},
    {'county': 'Hampshire', 'town': 'Fareham'},
    {'county': 'Oxfordshire', 'town': 'Faringdon'},
    {'county': 'Hampshire', 'town': 'Farnborough'},
    {'county': 'Surrey', 'town': 'Farnham'},
    {'county': 'Suffolk', 'town': 'Felixstowe'},
    {'county': 'Dyfed', 'town': 'Fishguard'},
    {'county': 'Co Tyrone', 'town': 'Fivemiletown'},
    {'county': 'Hampshire', 'town': 'Fleet'},
    {'county': 'Lancashire', 'town': 'Fleetwood'},
    {'county': 'Clwyd', 'town': 'Flint'},
    {'county': 'Kent', 'town': 'Folkestone'},
    {'county': 'Angus', 'town': 'Forfar'},
    {'county': 'Inverness-shire', 'town': 'Fort William'},
    {'county': 'Ross-shire', 'town': 'Fortrose'},
    {'county': 'Cornwall', 'town': 'Fowey'},
    {'county': 'Aberdeenshire', 'town': 'Fraserburgh'},
    {'county': 'Isle of Wight', 'town': 'Freshwater'},
    {'county': 'Essex', 'town': 'Frinton-on-Sea'},
    {'county': 'Somerset', 'town': 'Frome'},
    {'county': 'Lincolnshire', 'town': 'Gainsborough'},
    {'county': 'Ross-shire', 'town': 'Gairloch'},
    {'county': 'Selkirkshire', 'town': 'Galasheils'},
    {'county': 'Lancashire', 'town': 'Garstang'},
    {'county': 'Tyne & Wear', 'town': 'Gateshead'},
    {'county': 'Buckinghamshire', 'town': 'Gerrards Cross'},
    {'county': 'Dorset', 'town': 'Gillingham'},
    {'county': 'Kent', 'town': 'Gillingham'},
    {'county': 'South Ayrshire', 'town': 'Girvan'},
    {'county': 'Rotherham', 'town': 'Glamorgan'},
    {'county': 'Glasgow', 'town': 'Glasgow'},
    {'county': 'Somerset', 'town': 'Glastonbury'},
    {'county': 'Fife', 'town': 'Glenrothes'},
    {'county': 'Derbyshire', 'town': 'Glossop'},
    {'county': 'Gloucestershire', 'town': 'Gloucester'},
    {'county': 'Surrey', 'town': 'Godalming'},
    {'county': 'Surrey', 'town': 'Godstone'},
    {'county': 'East Riding of Yorkshire', 'town': 'Goole'},
    {'county': 'Cumbria', 'town': 'Gosforth'},
    {'county': 'Hampshire', 'town': 'Gosport'},
    {'county': 'Cumbria', 'town': 'Grange-over-Sands'},
    {'county': 'Midlothian', 'town': 'Grangemouth'},
    {'county': 'Lincolnshire', 'town': 'Grantham'},
    {'county': 'Kent', 'town': 'Gravesend'},
    {'county': 'Essex', 'town': 'Grays Thurrock'},
    {'county': 'Essex', 'town': 'Great Dunmow'},
    {'county': 'Buckinghamshire', 'town': 'Great Missenden'},
    {'county': 'Norfolk', 'town': 'Great Yarmouth'},
    {'county': 'Middlesex', 'town': 'Greenford'},
    {'county': 'Renfrewshire', 'town': 'Greenock'},
    {'county': 'Dumfriesshire', 'town': 'Gretna'},
    {'county': 'South Humberside', 'town': 'Grimsby'},
    {'county': 'Channel Islands', 'town': 'Guernsey'},
    {'county': 'Surrey', 'town': 'Guildford'},
    {'county': 'North Yorkshire', 'town': 'Guisborough'},
    {'county': 'West Yorkshire', 'town': 'Guiseley'},
    {'county': 'East Lothian', 'town': 'Gullane'},
    {'county': 'Lanark shire', 'town': 'Hamilton'},
    {'county': 'East Lothian', 'town': 'Haddington'},
    {'county': 'East Sussex', 'town': 'Hailsham'},
    {'county': 'West Midlands', 'town': 'Halesowen'},
    {'county': 'West Yorkshire', 'town': 'Halifax'},
    {'county': 'Essex', 'town': 'Halstead'},
    {'county': 'Northumberland', 'town': 'Haltwhistle'},
    {'county': 'Middlesex', 'town': 'Hampton'},
    {'county': 'Essex', 'town': 'Harlow'},
    {'county': 'Hertfordshire', 'town': 'Harpenden'},
    {'county': 'North Yorkshire', 'town': 'Harrogate'},
    {'county': 'Middlesex', 'town': 'Harrow'},
    {'county': 'Cleveland', 'town': 'Hartlepool'},
    {'county': 'Essex', 'town': 'Harwich'},
    {'county': 'Surrey', 'town': 'Haslemere'},
    {'county': 'West Sussex', 'town': 'Hassocks'},
    {'county': 'East Sussex', 'town': 'Hastings'},
    {'county': 'Hertfordshire', 'town': 'Hatfield'},
    {'county': 'Derbyshire', 'town': 'Hathersage'},
    {'county': 'Hampshire', 'town': 'Havant'},
    {'county': 'Pembrokeshire', 'town': 'Haverfordwest'},
    {'county': 'Suffolk', 'town': 'Haverhill'},
    {'county': 'Roxburghshire', 'town': 'Hawick'},
    {'county': 'Cumbria', 'town': 'Hawkshead'},
    {'county': 'Powys', 'town': 'Hay-on-Wye'},
    {'county': 'Middlesex', 'town': 'Hayes'},
    {'county': 'Hampshire', 'town': 'Hayling Island'},
    {'county': 'West Sussex', 'town': 'Haywards Heath'},
    {'county': 'Derbyshire', 'town': 'Heanor'},
    {'county': 'East Sussex', 'town': 'Heathfield'},
    {'county': 'West Yorkshire', 'town': 'Hebden Bridge'},
    {'county': 'Dunbartonshire', 'town': 'Helensburgh'},
    {'county': 'North Yorkshire', 'town': 'Helmsley'},
    {'county': 'Cornwall', 'town': 'Helston'},
    {'county': 'Hertfordshire', 'town': 'Hemel Hempstead'},
    {'county': 'West Sussex', 'town': 'Henfield'},
    {'county': 'Oxfordshire', 'town': 'Henley-on-Thames'},
    {'county': 'Hereford & Worcester', 'town': 'Hereford'},
    {'county': 'Kent', 'town': 'Herne Bay'},
    {'county': 'Hertfordshire', 'town': 'Hertford'},
    {'county': 'North Humberside', 'town': 'Hessle'},
    {'county': 'Northumberland', 'town': 'Hexham'},
    {'county': 'Lancashire', 'town': 'Heywood'},
    {'county': 'Buckinghamshire', 'town': 'High Wycombe'},
    {'county': 'Somerset', 'town': 'Highbridge'},
    {'county': 'Co Down', 'town': 'Hillsborough'},
    {'county': 'Leicestershire', 'town': 'Hinckley'},
    {'county': 'Surrey', 'town': 'Hindhead'},
    {'county': 'Hertfordshire', 'town': 'Hitchin'},
    {'county': 'Essex', 'town': 'Hockley'},
    {'county': 'Hertfordshire', 'town': 'Hoddesdon'},
    {'county': 'Lincolnshire', 'town': 'Holbeach'},
    {'county': 'Cheshire', 'town': 'Holmes Chapel'},
    {'county': 'Devon', 'town': 'Holsworthy'},
    {'county': 'Norfolk', 'town': 'Holt'},
    {'county': 'Gwynedd', 'town': 'Holyhead'},
    {'county': 'Co Down', 'town': 'Holywood'},
    {'county': 'Lincolnshire', 'town': 'Honington'},
    {'county': 'Devon', 'town': 'Honiton'},
    {'county': 'Hampshire', 'town': 'Hook'},
    {'county': 'Surrey', 'town': 'Horley'},
    {'county': 'Lancashire', 'town': 'Hornby'},
    {'county': 'Essex', 'town': 'Hornchurch'},
    {'county': 'East Riding of Yorkshire', 'town': 'Hornsea'},
    {'county': 'West Sussex', 'town': 'Horsham'},
    {'county': 'Tyne & Wear', 'town': 'Houghton le Spring'},
    {'county': 'Middlesex', 'town': 'Hounslow'},
    {'county': 'East Sussex', 'town': 'Hove'},
    {'county': 'West Yorkshire', 'town': 'Huddersfield'},
    {'county': 'North Humberside', 'town': 'Hull'},
    {'county': 'Berkshire', 'town': 'Hungerford'},
    {'county': 'Norfolk', 'town': 'Hunstanton'},
    {'county': 'Cambridgeshire', 'town': 'Huntingdon'},
    {'county': 'Aberdeenshire', 'town': 'Huntly'},
    {'county': 'Cheshire', 'town': 'Hyde'},
    {'county': 'Kent', 'town': 'Hythe'},
    {'county': 'Essex', 'town': 'Ilford'},
    {'county': 'Devon', 'town': 'Ilfracombe'},
    {'county': 'Derbyshire', 'town': 'Ilkeston'},
    {'county': 'West Yorkshire', 'town': 'Ilkley'},
    {'county': 'South Humberside', 'town': 'Immingham'},
    {'county': 'Essex', 'town': 'Ingatestone'},
    {'county': 'Aberdeenshire', 'town': 'Insch'},
    {'county': 'Argyll', 'town': 'Inveraray'},
    {'county': 'Inverness-shire', 'town': 'Inverness'},
    {'county': 'Aberdeenshire', 'town': 'Inverurie'},
    {'county': 'Isle of Iona', 'town': 'Iona'},
    {'county': 'Staffordshire', 'town': 'Ipstones'},
    {'county': 'Suffolk', 'town': 'Ipswich'},
    {'county': 'Shropshire', 'town': 'Ironbridge'},
    {'county': 'Isle of Wight', 'town': 'Isle of Wight'},
    {'county': 'Middlesex', 'town': 'Isleworth'},
    {'county': 'Channel Islands', 'town': 'Jersey'},
    {'county': 'Renfrewshire', 'town': 'Johnstone'},
    {'county': 'West Yorkshire', 'town': 'Keighley'},
    {'county': 'Roxburghshire', 'town': 'Kelso'},
    {'county': 'Cumbria', 'town': 'Kendal'},
    {'county': 'Warwickshire', 'town': 'Kenilworth'},
    {'county': 'Cumbria', 'town': 'Keswick'},
    {'county': 'Northamptonshire', 'town': 'Kettering'},
    {'county': 'Hereford & Worcester', 'town': 'Kidderminster'},
    {'county': 'Ayrshire', 'town': 'Kilbirnie'},
    {'county': 'Perthshire', 'town': 'Killin'},
    {'county': 'Lincolnshire', 'town': 'Killingholme'},
    {'county': 'Renfrewshire', 'town': 'Kilmacolm'},
    {'county': 'Ayrshire', 'town': 'Kilmarnock'},
    {'county': 'Norfolk', 'town': 'King\'s Lynn'},
    {'county': 'Hertfordshire', 'town': 'Kings Langley'},
    {'county': 'Devon', 'town': 'Kingsbridge'},
    {'county': 'Surrey', 'town': 'Kingston upon Thames'},
    {'county': 'West Midlands', 'town': 'Kingswinford'},
    {'county': 'Herefordshire', 'town': 'Kington'},
    {'county': 'Inverness-shire', 'town': 'Kingussie'},
    {'county': 'Cumbria', 'town': 'Kirkby Stephen'},
    {'county': 'Fife', 'town': 'Kirkcaldy'},
    {'county': 'Northumberland', 'town': 'Kirkwhelpington'},
    {'county': 'Angus', 'town': 'Kirriemuir'},
    {'county': 'Powys', 'town': 'Knighton'},
    {'county': 'Cheshire', 'town': 'Knutsford'},
    {'county': 'Ross-shire', 'town': 'Kyle'},
    {'county': 'Isle of Skye', 'town': 'Kyleakin'},
    {'county': 'Essex', 'town': 'Laindon'},
    {'county': 'Sutherland', 'town': 'Lairg'},
    {'county': 'Ceredigion', 'town': 'Lampeter'},
    {'county': 'Lanarkshire', 'town': 'Lanark'},
    {'county': 'Lancashire', 'town': 'Lancaster'},
    {'county': 'West Sussex', 'town': 'Lancing'},
    {'county': 'Warwickshire', 'town': 'Lapworth'},
    {'county': 'Stirlingshire', 'town': 'Larbert'},
    {'county': 'Caithness', 'town': 'Latheron'},
    {'county': 'Cornwall', 'town': 'Launceston'},
    {'county': 'Warwickshire', 'town': 'Leamington Spa'},
    {'county': 'Surrey', 'town': 'Leatherhead'},
    {'county': 'Hereford & Worcester', 'town': 'Ledbury'},
    {'county': 'West Yorkshire', 'town': 'Leeds'},
    {'county': 'Leicestershire', 'town': 'Leicester'},
    {'county': 'Lancashire', 'town': 'Leigh'},
    {'county': 'Essex', 'town': 'Leigh-on-Sea'},
    {'county': 'Bedfordshire', 'town': 'Leighton Buzzard'},
    {'county': 'Suffolk', 'town': 'Leiston'},
    {'county': 'Hereford & Worcester', 'town': 'Leominster'},
    {'county': 'Isle of Shetland', 'town': 'Lerwick'},
    {'county': 'Hertfordshire', 'town': 'Letchworth'},
    {'county': 'East Sussex', 'town': 'Lewes'},
    {'county': 'North Yorkshire', 'town': 'Leyburn'},
    {'county': 'Lancashire', 'town': 'Leyland'},
    {'county': 'Staffordshire', 'town': 'Lichfield'},
    {'county': 'Surrey', 'town': 'Lightwater'},
    {'county': 'Co Londonderry', 'town': 'Limavady'},
    {'county': 'Lincolnshire', 'town': 'Lincoln'},
    {'county': 'Surrey', 'town': 'Lingfield'},
    {'county': 'Hampshire', 'town': 'Liphook'},
    {'county': 'Co Antrim', 'town': 'Lisburn'},
    {'county': 'Cornwall', 'town': 'Liskeard'},
    {'county': 'Hampshire', 'town': 'Liss'},
    {'county': 'Lancashire', 'town': 'Littleborough'},
    {'county': 'West Sussex', 'town': 'Littlehampton'},
    {'county': 'Merseyside', 'town': 'Liverpool'},
    {'county': 'West Lothian', 'town': 'Livingston'},
    {'county': 'Ceredigion', 'town': 'Llanarth'},
    {'county': 'Gwynedd', 'town': 'Llanbedr'},
    {'county': 'Carmarthenshire', 'town': 'Llandeilo'},
    {'county': 'Carmarthenshire', 'town': 'Llandovery'},
    {'county': 'Powys', 'town': 'Llandrindod Wells'},
    {'county': 'Gwynedd', 'town': 'Llandudno'},
    {'county': 'Dyfed', 'town': 'Llandysul'},
    {'county': 'Dyfed', 'town': 'Llanelli'},
    {'county': 'Clwyd', 'town': 'Llangollen'},
    {'county': 'Powys', 'town': 'Llanidloes'},
    {'county': 'Ceredigion', 'town': 'Llanon'},
    {'county': 'Gwynedd', 'town': 'Llanrwst'},
    {'county': 'South Glamorgan', 'town': 'Llantwit'},
    {'county': 'Dyfed', 'town': 'Llanwrda'},
    {'county': 'Powys', 'town': 'Llanwrtyd Wells'},
    {'county': 'Midlothian', 'town': 'Loanhead'},
    {'county': 'Isle of Uist', 'town': 'Lochboisdale'},
    {'county': 'Ross-shire', 'town': 'Lochcarron'},
    {'county': 'Argyll', 'town': 'Lochgilphead'},
    {'county': 'Renfrewshire', 'town': 'Lochwinnoch'},
    {'county': 'Dumfriesshire', 'town': 'Lockerbie'},
    {'county': 'London', 'town': 'London'},
    {'county': 'Co Londonderry', 'town': 'Londonderry'},
    {'county': 'Leicestershire', 'town': 'Loughborough'},
    {'county': 'Essex', 'town': 'Loughton'},
    {'county': 'Lincolnshire', 'town': 'Louth'},
    {'county': 'Suffolk', 'town': 'Lowestoft'},
    {'county': 'Shropshire', 'town': 'Ludlow'},
    {'county': 'Co Antrim', 'town': 'Lurgan'},
    {'county': 'Bedfordshire', 'town': 'Luton'},
    {'county': 'Leicestershire', 'town': 'Lutterworth'},
    {'county': 'Gloucestershire', 'town': 'Lydney'},
    {'county': 'Hampshire', 'town': 'Lymington'},
    {'county': 'Hampshire', 'town': 'Lyndhurst'},
    {'county': 'Devon', 'town': 'Lynton'},
    {'county': 'Lancashire', 'town': 'Lytham StAnnes'},
    {'county': 'Cheshire', 'town': 'Macclesfield'},
    {'county': 'Powys', 'town': 'Machynlleth'},
    {'county': 'Cambridgeshire', 'town': 'Madingley'},
    {'county': 'Mid Glamorgan', 'town': 'Maesteg'},
    {'county': 'Co Londonderry', 'town': 'Magharafelt'},
    {'county': 'Berkshire', 'town': 'Maidenhead'},
    {'county': 'Kent', 'town': 'Maidstone'},
    {'county': 'Essex', 'town': 'Maldon'},
    {'county': 'Wiltshire', 'town': 'Malmesbury'},
    {'county': 'Cheshire', 'town': 'Malpas'},
    {'county': 'North Yorkshire', 'town': 'Malton'},
    {'county': 'Hereford & Worcester', 'town': 'Malvern'},
    {'county': 'Greater Manchester', 'town': 'Manchester'},
    {'county': 'Nottinghamshire', 'town': 'Mansfield'},
    {'county': 'Cambridgeshire', 'town': 'March'},
    {'county': 'Kent', 'town': 'Margate'},
    {'county': 'Shropshire', 'town': 'Market Drayton'},
    {'county': 'Leicestershire', 'town': 'Market Harborough'},
    {'county': 'Lincolnshire', 'town': 'Market Rasen'},
    {'county': 'East Riding of Yorkshire', 'town': 'Market Weighton'},
    {'county': 'Wiltshire', 'town': 'Marlborough'},
    {'county': 'Buckinghamshire', 'town': 'Marlow'},
    {'county': 'Lincolnshire', 'town': 'Martin'},
    {'county': 'Cumbria', 'town': 'Maryport'},
    {'county': 'Derbyshire', 'town': 'Matlock'},
    {'county': 'Aberdeenshire', 'town': 'Maud'},
    {'county': 'Kent', 'town': 'Medway'},
    {'county': 'Powys', 'town': 'Meifod'},
    {'county': 'Wiltshire', 'town': 'Melksham'},
    {'county': 'Leicestershire', 'town': 'Melton Mowbray'},
    {'county': 'Wiltshire', 'town': 'Mere'},
    {'county': 'West Midlands', 'town': 'Meriden'},
    {'county': 'Mid Glamorgan', 'town': 'Merthyr Tydfil'},
    {'county': 'South Yorkshire', 'town': 'Mexborough'},
    {'county': 'Cleveland', 'town': 'Middlesbrough'},
    {'county': 'Cheshire', 'town': 'Middlewich'},
    {'county': 'West Sussex', 'town': 'Midhurst'},
    {'county': 'Suffolk', 'town': 'Mildenhall'},
    {'county': 'Pembrokeshire', 'town': 'Milford Haven'},
    {'county': 'Buckinghamshire', 'town': 'Milton Keynes'},
    {'county': 'Somerset', 'town': 'Minehead'},
    {'county': 'West Yorkshire', 'town': 'Mirfield'},
    {'county': 'Surrey', 'town': 'Mitcham'},
    {'county': 'Gloucestershire', 'town': 'Mitcheldean'},
    {'county': 'Clwyd', 'town': 'Mold'},
    {'county': 'Gwent', 'town': 'Monmouth'},
    {'county': 'Powys', 'town': 'Montgomery'},
    {'county': 'Angus', 'town': 'Montrose'},
    {'county': 'Surrey', 'town': 'Morden'},
    {'county': 'Lancashire', 'town': 'Morecambe'},
    {'county': 'Devon', 'town': 'Moretonhampstead'},
    {'county': 'Northumberiand', 'town': 'Morpeth'},
    {'county': 'East Ayrshire', 'town': 'Moscow'},
    {'county': 'Lanarkshire', 'town': 'Motherwell'},
    {'county': 'Midlothian', 'town': 'Musselburgh'},
    {'county': 'Avon', 'town': 'Nailsea'},
    {'county': 'Inverness-shire', 'town': 'Nairn'},
    {'county': 'Cheshire', 'town': 'Nantwich'},
    {'county': 'Pembrokeshire', 'town': 'Narberth'},
    {'county': 'Neath Port Talbot', 'town': 'Neath'},
    {'county': 'Gwynedd', 'town': 'Nefyn'},
    {'county': 'Lancashire', 'town': 'Nelson'},
    {'county': 'Inverness-shire', 'town': 'Nethy Bridge'},
    {'county': 'Surrey', 'town': 'New Malden'},
    {'county': 'Derbyshire', 'town': 'New Mills'},
    {'county': 'Nottinghamshire', 'town': 'Newark'},
    {'county': 'Berkshire', 'town': 'Newbury'},
    {'county': 'Co Down', 'town': 'Newcastle'},
    {'county': 'Staffordshire', 'town': 'Newcastle'},
    {'county': 'Dyfed', 'town': 'Newcastle Emlyn'},
    {'county': 'Tyne & Wear', 'town': 'Newcastle upon Tyne'},
    {'county': 'Roxburghshire', 'town': 'Newcastleton'},
    {'county': 'Gloucestershire', 'town': 'Newent'},
    {'county': 'East Sussex', 'town': 'Newhaven'},
    {'county': 'Suffolk', 'town': 'Newmarket'},
    {'county': 'Gwent', 'town': 'Newport'},
    {'county': 'Isle of Wight', 'town': 'Newport'},
    {'county': 'Shropshire', 'town': 'Newport'},
    {'county': 'Buckinghamshire', 'town': 'Newport Pagnell'},
    {'county': 'Cornwall', 'town': 'Newquay'},
    {'county': 'Devon', 'town': 'Newton Abbot'},
    {'county': 'Powys', 'town': 'Newtown'},
    {'county': 'Merseyside', 'town': 'Newtown-le- Willows'},
    {'county': 'Co Antrim', 'town': 'Newtownabbey'},
    {'county': 'Co Down', 'town': 'Newtownards'},
    {'county': 'East Lothian', 'town': 'North Berwick'},
    {'county': 'Tyne & Wear', 'town': 'North Shields'},
    {'county': 'Norfolk', 'town': 'North Walsham'},
    {'county': 'North Yorkshire', 'town': 'Northallerton'},
    {'county': 'Northamptonshire', 'town': 'Northampton'},
    {'county': 'Cheshire', 'town': 'Northwich'},
    {'county': 'Middlesex', 'town': 'Northwood'},
    {'county': 'Norfolk', 'town': 'Norwich'},
    {'county': 'Nottinghamshire', 'town': 'Nottingham'},
    {'county': 'Nottinghamshire', 'town': 'Nottinghamshire'},
    {'county': 'Warwickshire', 'town': 'Nuneaton'},
    {'county': 'Leicestershire', 'town': 'Oakham'},
    {'county': 'Argyll', 'town': 'Oban'},
    {'county': 'Devon', 'town': 'Okehampton'},
    {'county': 'Lancashire', 'town': 'Oldham'},
    {'county': 'Co Tyrone', 'town': 'Omagh'},
    {'county': 'Essex', 'town': 'Ongar'},
    {'county': 'Lancashire', 'town': 'Ormskirk'},
    {'county': 'Kent', 'town': 'Orpington'},
    {'county': 'West Yorkshire', 'town': 'Ossett'},
    {'county': 'Shropshire', 'town': 'Oswestry'},
    {'county': 'West Yorkshire', 'town': 'Otley'},
    {'county': 'Oxfordshire', 'town': 'Oxford'},
    {'county': 'Surrey', 'town': 'Oxted'},
    {'county': 'Devon', 'town': 'Paignton'},
    {'county': 'Renfrewshire', 'town': 'Paisley'},
    {'county': 'Suffolk', 'town': 'Pakenham'},
    {'county': 'Cornwall', 'town': 'Par'},
    {'county': 'Dyfed', 'town': 'Pembroke'},
    {'county': 'South Glamorgan', 'town': 'Penarth'},
    {'county': 'Herefordshire', 'town': 'Pencombe'},
    {'county': 'Midlothian', 'town': 'Penicuik'},
    {'county': 'Gwynedd', 'town': 'Penmaenmawr'},
    {'county': 'Gwynedd', 'town': 'Penrhyndeudraeth'},
    {'county': 'Cumbria', 'town': 'Penrith'},
    {'county': 'Cornwall', 'town': 'Penryn'},
    {'county': 'Cornwall', 'town': 'Penzance'},
    {'county': 'Hereford & Worcester', 'town': 'Pershore'},
    {'county': 'Perthshire', 'town': 'Perth'},
    {'county': 'Cambridgeshire', 'town': 'Peterborough'},
    {'county': 'Aberdeenshire', 'town': 'Peterhead'},
    {'county': 'Hampshire', 'town': 'Petersfield'},
    {'county': 'West Sussex', 'town': 'Petworth'},
    {'county': 'East Sussex', 'town': 'Pevensey'},
    {'county': 'Wiltshire', 'town': 'Pewsey'},
    {'county': 'North Yorkshire', 'town': 'Pickering'},
    {'county': 'Middlesex', 'town': 'Pinner'},
    {'county': 'Perthshire', 'town': 'Pitlochry'},
    {'county': 'Devon', 'town': 'Plymouth'},
    {'county': 'East Riding of Yorkshire', 'town': 'Pocklington'},
    {'county': 'West Yorkshire', 'town': 'Pontefract'},
    {'county': 'Mid Glamorgan', 'town': 'Pontyclun'},
    {'county': 'Torfaen', 'town': 'Pontypool'},
    {'county': 'Mid Glamorgan', 'town': 'Pontypridd'},
    {'county': 'Dorset', 'town': 'Poole'},
    {'county': 'Cumbria', 'town': 'Pooley Bridge'},
    {'county': 'Cornwall', 'town': 'Port Isaac'},
    {'county': 'West Glamorgan', 'town': 'Port Talbot'},
    {'county': 'Mid Glamorgan', 'town': 'Porthcawl'},
    {'county': 'Gwynedd', 'town': 'Porthmadog'},
    {'county': 'Isle of Skye', 'town': 'Portree'},
    {'county': 'Co Antrim', 'town': 'Portrush'},
    {'county': 'Hampshire', 'town': 'Portsmouth'},
    {'county': 'Hertfordshire', 'town': 'Potters Bar'},
    {'county': 'Lancashire', 'town': 'Poulton-le-Fylde'},
    {'county': 'Merseyside', 'town': 'Prescot'},
    {'county': 'Clwyd', 'town': 'Prestatyn'},
    {'county': 'Lancashire', 'town': 'Preston'},
    {'county': 'Ayrshire', 'town': 'Prestwick'},
    {'county': 'Buckinghamshire', 'town': 'Princes Risborough'},
    {'county': 'Northumberland', 'town': 'Prudhoe'},
    {'county': 'West Sussex', 'town': 'Pulborough'},
    {'county': 'Surrey', 'town': 'Purley'},
    {'county': 'Gwynedd', 'town': 'Pwllheli'},
    {'county': 'Hertfordshire', 'town': 'Radlett'},
    {'county': 'Isle of Man', 'town': 'Ramsey'},
    {'county': 'Kent', 'town': 'Ramsgate'},
    {'county': 'Cumbria', 'town': 'Raughton Head'},
    {'county': 'Essex', 'town': 'Rayleigh'},
    {'county': 'Berkshire', 'town': 'Reading'},
    {'county': 'Cleveland', 'town': 'Redcar'},
    {'county': 'Hereford and', 'town': 'Redditch'},
    {'county': 'Surrey', 'town': 'Redhill'},
    {'county': 'Cornwall', 'town': 'Redruth'},
    {'county': 'Surrey', 'town': 'Reigate'},
    {'county': 'Nottmghamshire', 'town': 'Retford'},
    {'county': 'Clwyd', 'town': 'Rhyl'},
    {'county': 'North Yorkshire', 'town': 'Richmond'},
    {'county': 'Surrey', 'town': 'Richmond'},
    {'county': 'Hertfordshire', 'town': 'Rickmansworth'},
    {'county': 'Northumberland', 'town': 'Riding Mill'},
    {'county': 'Hampshire', 'town': 'Ringwood'},
    {'county': 'Derbyshire', 'town': 'Ripley'},
    {'county': 'North Yorkshire', 'town': 'Ripon'},
    {'county': 'East Sussex', 'town': 'Robertsbridge'},
    {'county': 'Lancashire', 'town': 'Rochdale'},
    {'county': 'Kent', 'town': 'Rochester'},
    {'county': 'Essex', 'town': 'Rochford'},
    {'county': 'Hampshire', 'town': 'Rockbourne'},
    {'county': 'Essex', 'town': 'Romford'},
    {'county': 'Hampshire', 'town': 'Romsey'},
    {'county': 'Herefordshire', 'town': 'Ross-on-Wye'},
    {'county': 'Lancashire', 'town': 'Rossendale'},
    {'county': 'Northumberland', 'town': 'Rothbury'},
    {'county': 'South Yorkshire', 'town': 'Rotherham'},
    {'county': 'Isle ofBute', 'town': 'Rothesay'},
    {'county': 'Hertfordshire', 'town': 'Royston'},
    {'county': 'Warwickshire', 'town': 'Rugby'},
    {'county': 'Staffordshire', 'town': 'Rugeley'},
    {'county': 'Middlesex', 'town': 'Ruislip'},
    {'county': 'Cheshire', 'town': 'Runcorn'},
    {'county': 'Northamptonshire', 'town': 'Rushden'},
    {'county': 'Clwyd', 'town': 'Ruthin'},
    {'county': 'East Sussex', 'town': 'Rye'},
    {'county': 'Tyne & Wear', 'town': 'Ryton'},
    {'county': 'Essex', 'town': 'Saffron Walden'},
    {'county': 'Lancashire', 'town': 'Salford'},
    {'county': 'Wiltshire', 'town': 'Salisbury'},
    {'county': 'Cornwall', 'town': 'Saltash'},
    {'county': 'Cleveland', 'town': 'Saltburn-by-the-Sea'},
    {'county': 'Ayrshire', 'town': 'Saltcoats'},
    {'county': 'Cheshire', 'town': 'Sandbach'},
    {'county': 'Berkshire', 'town': 'Sandhurst'},
    {'county': 'Isle of Wight', 'town': 'Sandown'},
    {'county': 'Kent', 'town': 'Sandwich'},
    {'county': 'Bedfordshire', 'town': 'Sandy'},
    {'county': 'Dumfriesshire', 'town': 'Sanquhar'},
    {'county': 'Hertfordshire', 'town': 'Sawbridgeworth'},
    {'county': 'Suffolk', 'town': 'Saxmundham'},
    {'county': 'North Yorkshire', 'town': 'Scarborough'},
    {'county': 'Isle of Tiree', 'town': 'Scarinish'},
    {'county': 'South Humberside', 'town': 'Scunthorpe'},
    {'county': 'East Sussex', 'town': 'Seaford'},
    {'county': 'Co Durham', 'town': 'Seaham'},
    {'county': 'Northumberland', 'town': 'Seahouses'},
    {'county': 'Devon', 'town': 'Seaton'},
    {'county': 'Cumbria', 'town': 'Sedbergh'},
    {'county': 'Co Durham', 'town': 'Sedgefield'},
    {'county': 'North Yorkshire', 'town': 'Selby'},
    {'county': 'Selkirkshire', 'town': 'Selkirk'},
    {'county': 'North Yorkshire', 'town': 'Settle'},
    {'county': 'Kent', 'town': 'Sevenoaks'},
    {'county': 'Wiltshire', 'town': 'Shaftesbury'},
    {'county': 'Cumbria', 'town': 'Shap'},
    {'county': 'Isle of Lewis', 'town': 'Shawbost'},
    {'county': 'South Yorkshire', 'town': 'Sheffield'},
    {'county': 'Middlesex', 'town': 'Shepperton'},
    {'county': 'Somerset', 'town': 'Shepton Mallet'},
    {'county': 'Dorset', 'town': 'Sherborne'},
    {'county': 'Norfolk', 'town': 'Sheringham'},
    {'county': 'Isle of Shetland', 'town': 'Shetland'},
    {'county': 'Shropshire', 'town': 'Shifnal'},
    {'county': 'West Yorkshire', 'town': 'Shipley'},
    {'county': 'Shropshire', 'town': 'Shrewsbury'},
    {'county': 'Kent', 'town': 'Sidcup'},
    {'county': 'Devon', 'town': 'Sidmouth'},
    {'county': 'Kent', 'town': 'Sittingbourne'},
    {'county': 'Lincolnshire', 'town': 'Skegness'},
    {'county': 'Lancashire', 'town': 'Skelmersdale'},
    {'county': 'North Yorkshire', 'town': 'Skipton'},
    {'county': 'Lincolnshire', 'town': 'Sleaford'},
    {'county': 'Berkshire', 'town': 'Slough'},
    {'county': 'West Midlands', 'town': 'Solihull'},
    {'county': 'Surrey', 'town': 'South Croydon'},
    {'county': 'West Lothian', 'town': 'South Queensferry'},
    {'county': 'Devon', 'town': 'South Molton'},
    {'county': 'Somerset', 'town': 'South Petherton'},
    {'county': 'Merseyside', 'town': 'South Wirral'},
    {'county': 'Middlesex', 'town': 'Southall'},
    {'county': 'Warwickshire', 'town': 'Southam'},
    {'county': 'Hampshire', 'town': 'Southampton'},
    {'county': 'Essex', 'town': 'Southend-on-Sea'},
    {'county': 'Essex', 'town': 'Southminster'},
    {'county': 'Merseyside', 'town': 'Southport'},
    {'county': 'Hampshire', 'town': 'Southsea'},
    {'county': 'Nottinghamshire', 'town': 'Southwell'},
    {'county': 'North Yorkshire', 'town': 'Sowerby'},
    {'county': 'Lincolnshire', 'town': 'Spalding'},
    {'county': 'Lincolnshire', 'town': 'Spilsby'},
    {'county': 'Hertfordshire', 'town': 'St Albans'},
    {'county': 'Fife', 'town': 'St Andrews'},
    {'county': 'Clwyd', 'town': 'St Asaph'},
    {'county': 'Cornwall', 'town': 'St Austell'},
    {'county': 'Carmarthenshire', 'town': 'St Clears'},
    {'county': 'Merseyside', 'town': 'St Helens'},
    {'county': 'Cornwall', 'town': 'St Ives'},
    {'county': 'East Sussex', 'town': 'St Leonards-on-Sea'},
    {'county': 'Staffordshire', 'town': 'Stafford'},
    {'county': 'Middlesex', 'town': 'Staines'},
    {'county': 'Lincolnshire', 'town': 'Stamford'},
    {'county': 'Essex', 'town': 'Stanford-le-Hope'},
    {'county': 'Middlesex', 'town': 'Stanmore'},
    {'county': 'Hertfordshire', 'town': 'Stevenage'},
    {'county': 'Stirlingshire', 'town': 'Stirling'},
    {'county': 'Cheshire', 'town': 'Stockport'},
    {'county': 'Northumberland', 'town': 'Stocksfield'},
    {'county': 'Cleveland', 'town': 'Stockton-on-Tees'},
    {'county': 'Staffordshire', 'town': 'Stoke-on-Trent'},
    {'county': 'Staffordshire', 'town': 'Stone'},
    {'county': 'Kincardineshire', 'town': 'Stonehaven'},
    {'county': 'Isle of Lewis', 'town': 'Stornoway'},
    {'county': 'West Midlands', 'town': 'Stourbridge'},
    {'county': 'Hereford & Worcester', 'town': 'Stourport-on-Severn'},
    {'county': 'Gloucestershire', 'town': 'Stow-on-the-Wold'},
    {'county': 'Suffolk', 'town': 'Stowmarket'},
    {'county': 'Wigtownshire', 'town': 'Stranraer'},
    {'county': 'Warwickshire', 'town': 'Stratford-upon-Avon'},
    {'county': 'Ross-shire', 'town': 'Strathcarron'},
    {'county': 'South Lanarkshire', 'town': 'Strathaven'},
    {'county': 'Ross-shire', 'town': 'Strathpeffer'},
    {'county': 'Somerset', 'town': 'Street'},
    {'county': 'Gloucestershire', 'town': 'Stroud'},
    {'county': 'Suffolk', 'town': 'Sudbury'},
    {'county': 'Middlesex', 'town': 'Sunbury-on-Thames'},
    {'county': 'Tyne & Wear', 'town': 'Sunderland'},
    {'county': 'Surrey', 'town': 'Surbiton'},
    {'county': 'Surrey', 'town': 'Sutton'},
    {'county': 'West Midlands', 'town': 'Sutton Coldfield'},
    {'county': 'Nottinghamshire', 'town': 'Sutton-in-Ashfield'},
    {'county': 'Norfolk', 'town': 'Swaffham'},
    {'county': 'Dorset', 'town': 'Swanage'},
    {'county': 'Kent', 'town': 'Swanley'},
    {'county': 'West Glamorgan', 'town': 'Swansea'},
    {'county': 'Wiltshire', 'town': 'Swindon'},
    {'county': 'Ross-shire', 'town': 'Tain'},
    {'county': 'Gwynedd', 'town': 'Talybont'},
    {'county': 'Staffordshire', 'town': 'Tamworth'},
    {'county': 'Argyll', 'town': 'Tarbert'},
    {'county': 'Cheshire', 'town': 'Tarporley'},
    {'county': 'Somerset', 'town': 'Taunton'},
    {'county': 'Devon', 'town': 'Tavistock'},
    {'county': 'Middlesex', 'town': 'Teddington'},
    {'county': 'Devon', 'town': 'Teignmouth'},
    {'county': 'Shropshire', 'town': 'Telford'},
    {'county': 'Somerset', 'town': 'Temple Cloud'},
    {'county': 'Somerset', 'town': 'Templecombe'},
    {'county': 'Dyfed', 'town': 'Tenby'},
    {'county': 'Gloucestershire', 'town': 'Tewkesbury'},
    {'county': 'Oxfordshire', 'town': 'Thame'},
    {'county': 'Kent', 'town': 'Thanet'},
    {'county': 'Berkshire', 'town': 'Thatcham'},
    {'county': 'Norfolk', 'town': 'Thetford'},
    {'county': 'North Yorkshire', 'town': 'Thirsk'},
    {'county': 'Surrey', 'town': 'Thornton Heath'},
    {'county': 'Caithness', 'town': 'Thurso'},
    {'county': 'Essex', 'town': 'Tilbury'},
    {'county': 'West Midlands', 'town': 'Tipton'},
    {'county': 'Devon', 'town': 'Tiverton'},
    {'county': 'West Yorkshire', 'town': 'Todmorden'},
    {'county': 'Kent', 'town': 'Tonbridge'},
    {'county': 'Devon', 'town': 'Torquay'},
    {'county': 'Devon', 'town': 'Torrington'},
    {'county': 'Isle of Wight', 'town': 'Totland Bay'},
    {'county': 'Northamptonshire', 'town': 'Towcester'},
    {'county': 'East Lothian', 'town': 'Tranent'},
    {'county': 'Gwent', 'town': 'Tredegar'},
    {'county': 'Hertfordshire', 'town': 'Tring'},
    {'county': 'Wiltshire', 'town': 'Trowbridge'},
    {'county': 'Cornwall', 'town': 'Truro'},
    {'county': 'Kent', 'town': 'Tunbridge Wells'},
    {'county': 'Aberdeenshire', 'town': 'Turriff'},
    {'county': 'Middlesex', 'town': 'Twickenham'},
    {'county': 'Gwynedd', 'town': 'Tywyn'},
    {'county': 'East Sussex', 'town': 'Uckfield'},
    {'county': 'Cumbria', 'town': 'Ulverston'},
    {'county': 'Devon', 'town': 'Umberleigh'},
    {'county': 'Staffordshire', 'town': 'Uttoxeter'},
    {'county': 'Middlesex', 'town': 'Uxbridge'},
    {'county': 'Isle ofWight', 'town': 'Ventnor'},
    {'county': 'Cornwall', 'town': 'Wadebridge'},
    {'county': 'West Yorkshire', 'town': 'Wakefield'},
    {'county': 'Merseyside', 'town': 'Wallasey'},
    {'county': 'Oxfordshire', 'town': 'Wallingford'},
    {'county': 'Surrey', 'town': 'Wallington'},
    {'county': 'West Midlands', 'town': 'Walsall'},
    {'county': 'Norfolk', 'town': 'Walsingham'},
    {'county': 'Hertfordshire', 'town': 'Waltham Cross'},
    {'county': 'Essex', 'town': 'Walton on the Naze'},
    {'county': 'Surrey', 'town': 'Walton-on-Thames'},
    {'county': 'Oxfordshire', 'town': 'Wantage'},
    {'county': 'Cambridgeshire', 'town': 'Warboys'},
    {'county': 'Hertfordshire', 'town': 'Ware'},
    {'county': 'Dorset', 'town': 'Wareham'},
    {'county': 'West Midlands', 'town': 'Warley'},
    {'county': 'Wiltshire', 'town': 'Warminster'},
    {'county': 'Cheshire', 'town': 'Warrington'},
    {'county': 'Warwickshire', 'town': 'Warwick'},
    {'county': 'Warwickshire', 'town': 'Warwickshire'},
    {'county': 'Tyne & Wear', 'town': 'Washington'},
    {'county': 'Somerset', 'town': 'Watchet'},
    {'county': 'Hertfordshire', 'town': 'Watford'},
    {'county': 'Somerset', 'town': 'Wedmore'},
    {'county': 'Kent', 'town': 'Welling'},
    {'county': 'Northamptonshire', 'town': 'Wellingborough'},
    {'county': 'Somerset', 'town': 'Wells'},
    {'county': 'Norfolk', 'town': 'Wells-next-the-Sea'},
    {'county': 'Powys', 'town': 'Welshpool'},
    {'county': 'Hertfordshire', 'town': 'Welwyn'},
    {'county': 'Hertfordshire', 'town': 'Welwyn Garden City'},
    {'county': 'Shropshire', 'town': 'Wem'},
    {'county': 'Middlesex', 'town': 'Wembley'},
    {'county': 'West Midlands', 'town': 'West Bromwich'},
    {'county': 'Surrey', 'town': 'West Byfleet'},
    {'county': 'Middlesex', 'town': 'West Drayton'},
    {'county': 'North Yorkshire', 'town': 'West Heslerton'},
    {'county': 'Ayrshire', 'town': 'West Kilbride'},
    {'county': 'Peeblesshire', 'town': 'West Linton'},
    {'county': 'Kent', 'town': 'West Malling'},
    {'county': 'Kent', 'town': 'West Wickham'},
    {'county': 'Wiltshire', 'town': 'Westbury'},
    {'county': 'Essex', 'town': 'Westcliff-on-Sea'},
    {'county': 'Kent', 'town': 'Westerham'},
    {'county': 'Avon', 'town': 'Weston-super-Mare'},
    {'county': 'West Yorkshire', 'town': 'Wetherby'},
    {'county': 'Surrey', 'town': 'Weybridge'},
    {'county': 'Dorset', 'town': 'Weymouth'},
    {'county': 'Nottinghamshire', 'town': 'Whatton'},
    {'county': 'North Yorkshire', 'town': 'Whitby'},
    {'county': 'Hampshire', 'town': 'Whitchurch'},
    {'county': 'Shropshire', 'town': 'Whitchurch'},
    {'county': 'Cumbria', 'town': 'Whitehaven'},
    {'county': 'Dyfed', 'town': 'Whitland'},
    {'county': 'Tyne & Wear', 'town': 'Whitley Bay'},
    {'county': 'Kent', 'town': 'Whitstable'},
    {'county': 'Caithness', 'town': 'Wick'},
    {'county': 'Essex', 'town': 'Wickford'},
    {'county': 'Lancashire', 'town': 'Wigan'},
    {'county': 'Cumbria', 'town': 'Wigton'},
    {'county': 'Cheshire', 'town': 'Wilmslow'},
    {'county': 'Dorset', 'town': 'Wimborne'},
    {'county': 'Somerset', 'town': 'Wincanton'},
    {'county': 'Hampshire', 'town': 'Winchester'},
    {'county': 'Cumbria', 'town': 'Windermere'},
    {'county': 'Berkshire', 'town': 'Windsor'},
    {'county': 'Somerset', 'town': 'Winscombe'},
    {'county': 'Merseyside', 'town': 'Wirral'},
    {'county': 'Cambridgeshire', 'town': 'Wisbech'},
    {'county': 'Lanarkshire', 'town': 'Wishaw'},
    {'county': 'Buckinghamshire', 'town': 'Witham'},
    {'county': 'Essex', 'town': 'Witham'},
    {'county': 'Oxfordshire', 'town': 'Witney'},
    {'county': 'Surrey', 'town': 'Woking'},
    {'county': 'Berkshire', 'town': 'Wokingham'},
    {'county': 'West Midlands', 'town': 'Wolverhampton'},
    {'county': 'Essex', 'town': 'Woodford Green'},
    {'county': 'Hereford & Worcester', 'town': 'Worcester'},
    {'county': 'Cumbria', 'town': 'Workington'},
    {'county': 'Nottinghamshire', 'town': 'Worksop'},
    {'county': 'Herefordshire', 'town': 'Wormbridge'},
    {'county': 'West Sussex', 'town': 'Worthing'},
    {'county': 'Gloucestershire', 'town': 'Wotton-under-Edge'},
    {'county': 'Clwyd', 'town': 'Wrexham'},
    {'county': 'Norfolk', 'town': 'Wymondham'},
    {'county': 'Surrey', 'town': 'Yateley'},
    {'county': 'Devon', 'town': 'Yelverton'},
    {'county': 'Somerset', 'town': 'Yeovil'},
    {'county': 'North Yorkshire', 'town': 'York'}
];

function flatMap (collection, mappingFn) {
    const flattened = [];

    for (const item of collection) {
        const value = mappingFn(item);

        if (typeof value[Symbol.iterator] === 'function') {
            flattened.push(...value);
            continue;
        }

        flattened.push(value);
    }
    return flattened;
}

function prop (key) {
  return function(obj) {
    if (obj == null) {
      return;
    }
    return obj[key];
  }
}
  
const groupedLocations = Map.groupBy(locations, ({town}) => town);

Tests:

Native JS flatMap
Array.from(groupedLocations) .flatMap(([k, v]) => v.length > 1 ? [[k, v.map(({county}) => county)]] : [])
Custom flatMap
flatMap( groupedLocations, ([k, v]) => v.length > 1 ? [[k, v.map(prop('county'))]]: [] )
lodash flatmap
_.flatMap( _.toArray(groupedLocations), ([k, v]) => v.length > 1 ? [[k, _.map(v, 'county')]]: [] )

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Native JS flatMap
Custom flatMap
lodash flatmap

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 13 days ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36

Browser/OS: Chrome 131 on Windows

View result in a separate tab

Test name	Executions per second
Native JS flatMap	19179.4 Ops/sec
Custom flatMap	33402.6 Ops/sec
lodash flatmap	22233.7 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated one month ago):

LLMs can make mistakes. Check important info.

The benchmark named "Custom Flatmap" compares the performance of JavaScript's native `flatMap` method to a custom `flatMap` function implemented with a loop. The custom function is designed to work with entries from a `Map` data structure, allowing for the transformation of data into a flattened array based on certain conditions.

### Benchmark Overview

**Tested Options:**
1. **Native JS `flatMap`:** This utilizes the built-in `flatMap` method, which allows us to map each element using a mapping function followed by flattening the result by one level.
2. **Custom `flatMap`:** This custom implementation iterates through the entries of a `Map`, applies a transformation function, and concatenates the results manually.

**Performance Results:**
- The custom `flatMap` function achieved a significantly higher execution rate of **56,718.55 executions per second**.
- The native `flatMap` performed with **19,338.14 executions per second**, indicating that the custom implementation was nearly three times faster.

### Pros and Cons of Each Approach

**Native JS `flatMap`:**

*Pros:*
- Simplicity: Easy to read and succinct.
- Built-in: Uses standardized JavaScript functionality, thus benefiting from ongoing optimizations in the JavaScript engine.
- Less error-prone: Higher-level abstraction means fewer chances for logical errors compared to manual implementations.

*Cons:*
- Performance: In this benchmark, the native method was less performant than the custom implementation. This may not be typical across all scenarios, but it shows potential performance limits for native functions in specific contexts.
- Less control: Limited customization compared to manual implementations.

**Custom `flatMap`:**

*Pros:*
- Performance: The custom implementation exhibited superior performance in this benchmark. Custom optimizations can be made based on specific use cases.
- Flexibility: Allows for specific customization tailored to the problem at hand.

*Cons:*
- Complexity: Manual implementations can become convoluted, increasing the risk of bugs and making the code harder to read and maintain.
- Maintenance: Vendors (browsers) may not have optimized a custom function as thoroughly as native solutions, affecting cross-browser performance variances.

### Additional Considerations

1. **Readability vs. Performance:** In general, developers may need to balance between code readability and performance needs. While custom solutions can provide performance boosts, they often come at the cost of increased complexity.
2. **Use Cases:** Depending on how the custom `flatMap` is structured, it might be more suitable for specific tasks where performance is crucial. This is particularly relevant in cases with large data sets or in performance-critical applications.
3. **Browser Compatibility:** Native methods are more reliable in terms of compatibility and long-term support due to their standardization, while custom functions might lead to issues if they rely on less-common features or assumptions.
4. **Data Structures:** The use of `Map` is noteworthy. Maps are beneficial when frequent additions/removals are needed, unlike traditional objects, and in this context, it allowed a better organization of locations based on towns.

### Alternatives

If you are looking for alternatives to achieve similar results for flattening an array in JavaScript, consider:

1. **Using Other Array Methods:**
   - While both `flatMap()` and a custom `flatMap` work, you can also use `map()` followed by `reduce()` with `concat()` for achieving similar results, though it may offer worse performance.
   
2. **Performance-focused libraries:**
   - Libraries like Lodash provide utilities for array manipulation, possibly improving both readability and performance. Methods like `_.flatMap()` from Lodash can be useful, but check performance against a custom solution.

3. **Data Processing Libraries:**
   - Libraries such as RxJS or even framework-specific approaches (like React or Vue) may have their data processing techniques that are optimized within a larger framework context.

In conclusion, selecting between native and custom implementations depends heavily on the specific use case, data set size, and the importance of performance versus readability within the project's context.

Related benchmarks:

Custom Flatmap (version: 4)

Comparison between using JS' native flatMap, a custom flatMap, and lodash's flatMap. Custom flatMap works with all Iterable types, so need to convert Map's to arrays before flatMapping.

Comparing performance of: Native JS flatMap vs Custom flatMap vs lodash flatmap

Created: one month ago by: Registered User

Jump to the latest result

Native JS flatMap

Custom flatMap

lodash flatmap

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated one month ago):