Question:

Method: Use DFS to traverse all possible nodes, and then remove repeated cases through SET, and finally get all the results that meet the requirements.

package com.eric.leetcode class SubsetsII { fun subsetsWithDup(nums: IntArray): List<List<Int>> { val result = mutableSetOf<List<Int>>() result.add(mutableListOf()) for (index in nums.indices) { dfs(nums, index, mutableListOf(), result) } return result.toList() } private fun dfs(nums: IntArray, cur: Int, list: MutableList<Int>, result: MutableSet<List<Int>>) { val newList = mutableListOf<Int>() newList.addAll(list) newList.add(nums[cur]) newList.sort() result.add(newList) for (index in cur + 1.. nums.lastIndex) { dfs(nums, index, newList, result) } } } fun main() { val input = intArrayOf(1, 2, 2) val subsetsII = SubsetsII() subsetsII.subsetsWithDup(input) }Copy the code

Feel free to communicate if you have any questions

Specific code implementation can refer to Github