Three Sum

class Solution {
public:
    vector<vector<int>> threeSum(vector<int>& nums) {
        sort(nums.begin(), nums.end());
        set<vector<int>>ans;
        for(int i = 0;i<nums.size();i++){
            if(i && nums[i] == nums[i-1]) continue;
            int j = i+1, k = nums.size()-1;
            while(j<k){
                if(nums[i] + nums[j] + nums[k]< 0){
                    j++;
                } else if(nums[i] + nums[j] + nums[k] > 0) {
                    k--;
                } else {
                    ans.insert({nums[i],nums[j],nums[k]});
                    j++;
                    k--;
                }
            }
        }
        vector<vector<int>>ans1;
        for(auto it:ans){
            ans1.push_back(it);
        }
        return ans1;
    }
};

// Question Link:- https://leetcode.com/problems/3sum/description/