前端 JS 经典：最长递增子序列

function LIS(nums) {
  if (nums.length === 0) {
    return [];
  }
  let results = [[nums[0]]];
  for (let i = 1; i < nums.length; i++) {
    const n = nums[i];
    _update(n);
  }
  function _update(n) {
    for (let i = results.length - 1; i >= 0; i--) {
      const line = results[i];
      const tail = line[line.length - 1];
      if (n > tail) {
        results[i + 1] = [...line, n];
        break;
      } else if (n < tail && i === 0) {
        results[i] = [n];
      }
    }
  }
  return results[results.length - 1];
}