90. Subsets II

Given an integer array nums that may contain duplicates, return all possible subsets (the power set).

The solution set must not contain duplicate subsets. Return the solution in any order.

 

Example 1:

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

Example 2:

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

 

Constraints:

  • 1 <= nums.length <= 10
  • -10 <= nums[i] <= 10

90. Subsets II
struct Solution;

impl Solution {
    fn subsets_with_dup(mut nums: Vec<i32>) -> Vec<Vec<i32>> {
        nums.sort_unstable();
        let n = nums.len();
        let mut cur = vec![];
        let mut res = vec![];
        Self::dfs(0, &mut cur, &mut res, &nums, n);
        res
    }

    fn dfs(start: usize, cur: &mut Vec<i32>, all: &mut Vec<Vec<i32>>, nums: &[i32], n: usize) {
        all.push(cur.to_vec());
        if start == n {
            return;
        }
        for i in start..n {
            if i > start && nums[i] == nums[i - 1] {
                continue;
            }
            cur.push(nums[i]);
            Self::dfs(i + 1, cur, all, nums, n);
            cur.pop();
        }
    }
}

#[test]
fn test() {
    let nums = vec![1, 2, 2];
    let mut res = vec_vec_i32![[2], [1], [1, 2, 2], [2, 2], [1, 2], []];
    res.sort_unstable();
    assert_eq!(Solution::subsets_with_dup(nums), res);
}