46\. Permutations
# 46. Permutations (opens new window)
# Description
Difficulty: Medium
Related Topics: Array (opens new window), Backtracking (opens new window)
Given an array nums
of distinct integers, return all the possible permutations. You can return the answer in any order.
Example 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]]
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Example 2:
Input: nums = [0,1]
Output: [[0,1],[1,0]]
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Example 3:
Input: nums = [1]
Output: [[1]]
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Constraints:
1 <= nums.length <= 6
-10 <= nums[i] <= 10
- All the integers of
nums
are unique.
# Solution
Language: JavaScript
/**
* @param {number[]} nums
* @return {number[][]}
* 广度优先遍历
* 深度优先遍历
*/
var permute = function(nums) {
nums.sort((a, b) => a - b);
const ans = [];
const backtrack = (path = []) => {
if (path.length === nums.length) return ans.push([...path]);
nums.forEach(num => {
if (!path.includes(num)) backtrack([...path, num]);
})
}
backtrack();
return ans;
};
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