31-下一个排列

public void nextPermutation(int[] nums) {
    for (int i = nums.length - 2; i >= 0; i--) {
        if (nums[i] < nums[i + 1]){
            Arrays.sort(nums, i + 1, nums.length);
            for (int j = i + 1; j < nums.length; j++) {
                if (nums[j] > nums[i]){
                    int temp = nums[i];
                    nums[i] = nums[j];
                    nums[j] = temp;
                    return ;
                }
            }
        }
    }
    Arrays.sort(nums);	//题目要求已经是最大排列的话，变回最小
}