[31] 下一个排列

/**
 * @param {number[]} nums
 * @return {void} Do not return anything, modify nums in-place instead.
 */
var nextPermutation = function (nums) {
  const nlen = nums.length
  for (let i = nlen - 2; i >= 0; i--) {
    const temp = nums[i];
    for (let j = i + 1; j <= nlen - 1; j++) {
      if (nums[j] > nums[i]) {
        nums[i] = nums[j];
        nums[j] = temp;
        for (let k = j + 1; j <= nlen - 1; k++) {
          if (nums[k] < temp) {
            nums[k - 1] = nums[k]
          } else {
            nums[k - 1] = temp
            break
          }
        }
        return nums
      }
    }
    nums.splice(i, 1)
    nums.push(temp)
  }
  return nums
};