문제

리트코드 46. Permutations
난이도: ⭐⭐

Given an array nums of distinct integers, return all the possible permutations. You can return the answer in any order.
(서로 다른 정수를 입력받아 가능한 모든 순열을 리턴하라.)

예시 1

Input: nums = [1,2,3]
Output: [[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]]

예시 2

Input: nums = [0,1]
Output: [[0,1],[1,0]]

풀이 1: DFS를 활용한 순열 생성

class Solution:
    def permute(self, nums: List[int]) -> List[List[int]]:
        results = []
        prev_elements = []
        
        def dfs(elements):
            if len(elements) == 0:
                results.append(prev_elements[:])
                
            for e in elements:
                next_elements = elements[:]
                next_elements.remove(e)
                
                prev_elements.append(e)
                dfs(next_elements)
                prev_elements.pop()
        
        dfs(nums)
        
        return results