Here, We see Combination Sum II problem Solution. This Leetcode problem is done in many programming languages like C++, Java, JavaScript, Python, etc., with different approaches.

Combination Sum II LeetCode Solution
Problem Statement ->
Given a collection of candidate numbers (candidates) and a target number (target), find all unique combinations in candidates where the candidate numbers sum to target.
Example 1: Input: candidates = [10,1,2,7,6,1,5], target = 8 Output: [ [1,1,6], [1,2,5], [1,7], [2,6] ]
Example 2: Input: candidates = [2,5,2,1,2], target = 5 Output: [ [1,2,2], [5] ]
Combination Sum II Leetcode Solution C++ ->
class Solution {
public:
vector<vector<int>> result;
vector<vector<int>> combinationSum2(vector<int>& candidates, int target) {
vector<int> curr;
int n = candidates.size();
sort(candidates.begin(), candidates.end());
comsum(curr, target, 0, candidates, 0, n);
return result;
}
void comsum(vector<int> &curr, int target, int sum, vector<int> &candidates, int curInd, int n){
if(target == sum){
result.push_back(curr);
return;
}
else if(sum>target){
return;
}
for(int i = curInd; i < n; i++){
if(i != curInd && candidates[i]==candidates[i-1])
continue;
sum += candidates[i];
curr.push_back(candidates[i]);
comsum(curr, target, sum, candidates, i+1, n);
sum -= candidates[i];
curr.pop_back();
}
}
};
Code language: C++ (cpp)
Combination Sum II Leetcode Solution Java ->
class Solution {
public List<List<Integer>> combinationSum2(int[] candidates, int target) {
List<List<Integer>> res = new ArrayList<>();
List<Integer> smallAns = new ArrayList<>();
Arrays.sort(candidates);
combinationSum2(candidates, target, 0, smallAns, res);
return res;
}
public int combinationSum2(int[] arr, int tar, int idx, List<Integer> smallAns, List<List<Integer>> res) {
if (tar == 0) {
ArrayList<Integer> base = new ArrayList<>(smallAns);
res.add(base);
return 1;
}
boolean[] visited = new boolean[50];
int count = 0;
for (int i = idx; i < arr.length; ++i) {
if (!visited[arr[i]] && tar - arr[i] >= 0) {
visited[arr[i]] = true;
smallAns.add(arr[i]);
count += combinationSum2(arr, tar - arr[i], i + 1, smallAns, res);
smallAns.remove(smallAns.size() - 1);
}
}
return count;
}
}
Code language: Java (java)
Combination Sum II Leetcode Solution JavaScript ->
var combinationSum2 = function(candidates, target) {
if (!candidates) {
return [];
}
if (target === 0) {
return [[]];
}
candidates.sort((a,b) => { return a - b});
let paths = [];
let find = function (t, p, i) {
if (t === 0) {
paths.push(p);
return;
} else {
while (i < candidates.length && t - candidates[i] >= 0) {
find(t - candidates[i], [...p, candidates[i]], i + 1)
i++;
while (candidates[i - 1] === candidates[i]) {
i++;
}
}
}
}
find (target, [], 0);
return paths;
};
Code language: JavaScript (javascript)
Combination Sum II Leetcode Solution Python ->
class Solution(object):
def combinationSum2(self, candidates, target):
candidates.sort()
result = []
self.combine_sum_2(candidates, 0, [], result, target)
return result
def combine_sum_2(self, nums, start, path, result, target):
if not target:
result.append(path)
return
for i in xrange(start, len(nums)):
if i > start and nums[i] == nums[i - 1]:
continue
if nums[i] > target:
break
self.combine_sum_2(nums, i + 1, path + [nums[i]],
result, target - nums[i])
Code language: Python (python)