CombinationSumII.java

//LeetCode 40. Combination Sum II
//Question - https://leetcode.com/problems/combination-sum-ii/

classSolution {
publicList<List<Integer>> combinationSum2(int[] nums, inttarget) {
List<List<Integer>> res = newArrayList<>();

Arrays.sort(nums);
helper(nums, 0, 0, target, newArrayList<>(), res);
returnres;

 }

publicvoidhelper(intnums[], intindex, intsum, inttarget, List<Integer> l, List<List<Integer>> res){
if(sum > target) return;
elseif(sum == target){
res.add(newArrayList<>(l));
return;
 }

for(inti = index ; i < nums.length ; i++){
if(i > index && nums[i] == nums[i-1]) continue;

l.add(nums[i]);
helper(nums, i + 1, sum + nums[i], target, l, res);
l.remove(l.size()-1);
 }
 }
}