​

function chunk(input, size) {

  const length= input.length;

  const chunksLenght= length/size;

  if(chunksLenght<0){

    return input;

  }

  const chunks=[];

  let index = 0;

  for(let i =0 ;i < chunksLenght ; i++){

    chunks.push(input.slice(index , index + size));

    index += size;

  }

  // the remainig 

  if(index < length){

     chunks.push(input.slice(index , length));

  }

  return chunks;

};