题目
给定一个不含重复数字的数组 nums ,返回其 所有可能的全排列 。你可以 按任意顺序 返回答案。
示例 1:
输入:nums = [1,2,3]
输出:[[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]]
解
class Solution {public List<List<Integer>> permute(int[] nums) {List<List<Integer>> result = new ArrayList<>();int n = nums.length;boolean[] used = new boolean[n];LinkedList<Integer> path = new LinkedList<>();dfs(nums, 0, used, path, result);return result;}public void dfs(int[] nums, int index, boolean[] used, LinkedList<Integer> path, List<List<Integer>> res) {if (index == nums.length) {res.add(new LinkedList(path));return;}for (int i = 0; i < nums.length; i++) {if (used[i]) {continue;}path.add(nums[i]);used[i] = true;dfs(nums, index + 1, used, path, res);used[i] = false;path.removeLast();}}
}