Answer 1

  let arr = [2, 10, 3, 4, 5, 11, 10, 11, 20];

  arr = Array.from(new Set(arr)).sort((a, b) => a - b);

  let start = 0;
  for(let i = 0; i < arr.length - 1; i ++){
    if (arr[i + 1] - arr[i] > 1) {
      console.log(arr.slice(start,i + 1));
      start = i + 1;
    }
  }
  console.log(arr.slice(start,arr.length));

以为求连续 + 1