【算法题7】寻找下一个排列

 1 class Solution:
 2     def nextPermutation(self, nums):
 3         """
 4         :type nums: List[int]
 5         :rtype: void Do not return anything, modify nums in-place instead.
 6         """
 7         right=len(nums)-1
 8         while nums[right]<=nums[right-1] and right-1>=0:
 9             right -=1
10         if right==0:
11             return self.reverse(nums,0,len(nums)-1)
12         
13         privot=right-1
14         
15         successor=0
16         for i in range(len(nums)-1,privot,-1):
17             if nums[i]>nums[privot]:
18                 successor=i
19                 break
20         nums[privot],nums[successor]=nums[successor],nums[privot]
21         self.reverse(nums,privot+1,len(nums)-1)
22         return nums
23 
24     def reverse(self,nums,l,r):
25         while l<r:
26             nums[l],nums[r]=nums[r],nums[l]
27             l+=1
28             r-=1