Use backtracking: maintain a set of already-placed elements and, at each position, try every unused element.

Permutations

medium

Acceptance: 53%

BacktrackingArrays

Given an array of distinct integers, generate every possible ordering (permutation) of those integers. The results may appear in any sequence.

Example 1:

Input:nums = [7,8,9]

Output:[[7,8,9],[7,9,8],[8,7,9],[8,9,7],[9,7,8],[9,8,7]]

Example 2:

Input:nums = [4,5]

Output:[[4,5],[5,4]]

1234567

import java.util.*;

public class Main {
    public static void main(String[] args) {
        // Write your solution here
    }
}

import java.util.*;

public class Main {
    public static void main(String[] args) {
        // Write your solution here
    }
}