subsets.js

/*
78. Subsets
Given an integer array nums of unique elements, 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 = [1,2,3]
Output: [[],[1],[2],[1,2],[3],[1,3],[2,3],[1,2,3]]

Example 2:
Input: nums = [0]
Output: [[],[0]]
*/

/**
 * @param {number[]} nums
 * @return {number[][]}
 */

// Using Backtracking

var subsets = function (nums) {
    // global result
    const result = []

    // dfs recursive helper
    const dfs = (i, nums, slate) => {
        // base case
        if (i === nums.length) {
            result.push(slate.slice())
            return
        }

        // dfs recursive case

        // exclude
        dfs(i + 1, nums, slate)

        // include
        slate.push(nums[i])
        dfs(i + 1, nums, slate)
        slate.pop()
    }

    dfs(0, nums, [])
    return result
};

console.log(subsets([1, 2, 3]))