90. Subsets II

var subsetsWithDup = function (nums) {
	const result = [],
		len = nums.length
	nums = nums.sort((a, b) => a - b)

	function subsetHelper(i, slate) {
		if (len === i) {
			result.push(slate.slice(0))
			return
		}

		let count = 1,
			j = i + 1

		while (j < len && nums[j] === nums[i]) {
			count++
			j++
		}

		for (let copies = 0; copies < count + 1; copies++) {
			for (let op = 0; op < copies; op++) {
				slate.push(nums[i])
			}

			subsetHelper(count + i, slate)

			for (let op = 0; op < copies; op++) {
				slate.pop()
			}
		}
	}

	subsetHelper(0, [])
	return result
}

// Tests
console.log(subsetsWithDup([1, 2, 3]))
console.log(subsetsWithDup([1, 2, 2, 2]))