31. Next Permutation

31. Next Permutation

Medium

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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

class Solution:
    def nextPermutation(self, nums: List[int]) -> None:
        """
        Do not return anything, modify nums in-place instead.
        """
        i = len(nums) - 2
        flag = False

        while i>=0:
            if nums[i] < nums[i+1]:
                flag = True
                break
            i -= 1

        if not flag:
            nums.sort()
            return nums
            print(nums)
        else:
            j = len(nums)-1
            while nums[j] <=nums[i] and j > i:
                j -= 1

            nums[i], nums[j] = nums[j], nums[i]
            nums[i+1:] = nums[i+1:][::-1]

- python은 inplace swap이 가능한 점

- 정렬 알고리즘 중 이러한 정렬 알고리즘도 있다는것..