标签：index amp ges constrain call use str sorted break
Implement next permutation, which rearranges numbers into the lexicographically next greater permutation of numbers. If such an arrangement is not possible, it must rearrange it as the lowest possible order (i.e., sorted in ascending order). The replacement must be in place and use only constant extra memory. Example 1: Input: nums = [1,2,3] Output: [1,3,2] Example 2: Input: nums = [3,2,1] Output: [1,2,3] Example 3: Input: nums = [1,1,5] Output: [1,5,1] Example 4: Input: nums = [1] Output: [1] Constraints: 1 <= nums.length <= 100 0 <= nums[i] <= 100
从右至左， 找出规律
class Solution { public void nextPermutation(int[] nums) { for (int i = nums.length - 2; i >= 0; i--) { if (nums[i] < nums[i+1]) { swap(nums, i); reverse(nums, i); break; } if(i == 0) { reverse(nums, -1); } } } public void swap (int[] nums, int index) { for (int i = nums.length - 1; i >index; i--) { if (nums[i] > nums[index]) { int temp = nums[index]; nums[index] = nums[i]; nums[i] = temp; break; } } } public void reverse(int[] nums, int index) { int i = index + 1; int j = nums.length - 1; while( j > i) { int temp = nums[i]; nums[i] = nums[j]; nums[j] = temp; i++; j--; } } }
标签：index amp ges constrain call use str sorted break
原文地址：https://www.cnblogs.com/incrediblechangshuo/p/14397734.html
