moveZeroes benchmark

moveZeroes_bench.js

const fs = require('node:fs');

const moveZeroes = (nums) => {
  let write = 0;
  for (let read = 0; read < nums.length; ++read)
    if (nums[read] !== 0)
      nums[write++] = nums[read];
  for (; write < nums.length; ++write)
    nums[write] = 0;
  return nums;
}

const moveZeroes_ = (nums) => {
  return nums.sort( (a, b) => {
    return ( a == 0 ) || -( b == 0);
  });
}

try {
  const data = fs.readFileSync('./input.txt', 'utf8');
  const numbers = data.split('\n').map(Number);
  console.time();
  moveZeroes(numbers);
  console.timeEnd();
  console.time();
  moveZeroes_(numbers);
  console.timeEnd();
} catch (err) {
  console.error(err);
}

// Output:
//
// $ node writeZeros.js
// default: 11.923ms
// default: 48.693ms
//
// Conclusion: version which uses built in array.sort is 4x slower.

input generated with:
echo "$(for n in $(seq 1 1000000); do echo 0; done; seq 1 1000000)" | shuf | tee input.txt

ran on apple m1 pro