3Sum.cpp

class Solution {
public:
    vector<vector<int>> threeSum(vector<int>& nums) {
        int n = nums.size();
        int target = 0;
        sort(nums.begin(), nums.end());
        set<vector<int>> s;
        vector<vector<int>> output;

        for(int i = 0; i<n;i++){
            int j = i+1;
            int k = n-1;
            while(j<k){
                int sum = nums[i] + nums[j] + nums[k];
                if (sum == target) {
                    s.insert({nums[i], nums[j], nums[k]});
                    j++;
                    k--;
                } else if (sum < target) {
                    j++;
                } else {
                    k--;
                }
            }
        }
        for(auto triplets : s)
            output.push_back(triplets);
        return output;
            
        

    }
};