Arturchick

const closest = distances.reduce((acc, val) => {
  if (acc.distance === 0) return val;
  if (val.distance === 0) return acc;
  return acc.distance < val.distance ? acc : val;
});

const xxx = ([...str]) => [...new Set(Array.from(
  { length: str.length * 10 },
  (n, i) => str.map((m, j) => (j === (i / 10 | 0)) ? i % 10 : m).join('')
))];

function xxx(str) {
  const arr = str.split('');
  const result = [ str ];

  for (const [ i, n ] of arr.entries()) {
    for (let j = 0; j < 10; j++) {
      if (j !== +n) {
        arr[i] = j;
        result.push(arr.join(''));
      }
    }

    arr[i] = n;
  }

  return result;
}