[JS] Subsets II

🔒 문제 (LeetCode 90)

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.

Constraints:

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

 

🌊 입출력

Example 1:

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

Example 2:

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

 

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🔑 해결

🌌 알고리즘 - Backtracking (DFS)

/**
 * @param {number[]} nums
 * @return {number[][]}
 */
var subsetsWithDup = function(nums) {
    nums.sort((a, b) => a-b)
    const result = []
    
    const backTracking = (subset, arr) => {
        result.push([...subset])
        
        for(let i = 0; i < arr.length; i++) {
            if(i === 0 || arr[i] !== arr[i-1]) {
                subset.push(arr[i])
                backTracking(subset, arr.slice(i+1))
                subset.pop();
            }
        }
    }
    
    backTracking([], nums)
    
    return result
};