/**

 * Gets a random number between 2 bigInts

 * @param {BigInt} max

 * @param {BigInt} [min=0n]

 * @returns {BigInt}

 */

function randomBetween(max, min = 0n) {

  max = BigInt(max);

  min = BigInt(min);

  if (max < min) {

    [max, min] = [min, max]

  }

  const range = max - min;

  const count = calculatePrecision(range);

  let random = new Array(Number(count))

    .fill(0)

    .map(() => BigInt(Math.floor(Math.random() * (2 ** 32))))

    .map((int, index) => int << (BigInt(index) * 32n))

    .reduce((acc, int) => acc + int, 0n);

​

​

  let bitCount = countBits(range);

  let minRandom = random >> ((32n * count) - bitCount);

  if (minRandom > range) return randomBetween(max, min);

  else return minRandom + min;

}

​

function calculatePrecision(range) {

  const result = range >> 32n;

  if (result >= 1n) {

    return calculatePrecision(result) + 1n;

  }

  return 1n;

}

​

function countBits(range) {

  const result = range >> 1n;

  if (result >= 1n) {

    return countBits(result) + 1n;

  }

  return 1n;

}

​

const a = randomBetween(10n ** 20n, 10n ** 19n)

const b = randomBetween(10n ** 20n, 10n ** 19n)

aBigInt = a;

bBigInt = b;

aString = a.toString();

bString = b.toString();

aFloat = Number(a);

bFloat = Number(b);