leetcode-----31. 下一个排列

• 链接：https://leetcode-cn.com/problems/next-permutation/

代码

class Solution {
public:
    void nextPermutation(vector<int>& nums) {
        int k = nums.size() - 1;
        while (k > 0 && nums[k - 1] >= nums[k]) k--;
        if (k <= 0) {
            reverse(nums.begin(), nums.end());
        } else {
            int t = k;
            while (t < nums.size() && nums[t] > nums[k - 1]) t++;
            swap(nums[t - 1], nums[k - 1]);
            reverse(nums.begin() + k, nums.end());
        }
    }
};