Shows Time limit exceed in 3Sum leetcode problem if i write it in function but it didn't show TLE without function

#1

This code shows TLE.

vector<vector<int>> twoSum(vector<int>& nums ,int index,int target,vector<vector<int>>& res){

    int left = index;
    int right = nums.size()-1;
    
    while(left < right){
        
        
        int sum = nums[left] + nums[right];
        if(sum < target){
            left++;
        }
        else if(sum > target){
            right--;
        }
        else{
            res.push_back({-target,nums[left],nums[right]});
            while(left < right && res.back()[1] == nums[left]) left++;
            while(left < right && res.back()[2] == nums[right]) right--;
        }
    }
    return res;
}



 vector<vector<int>> threeSum(vector<int>& nums) {
    vector<vector<int>> res;
    sort(nums.begin(),nums.end());
    for(int i=0 ; i < nums.size() - 2; ++i){
        if(i > 0 && nums[i-1] == nums[i]) continue;
        res = twoSum(nums,i+1,-nums[i],res);
    }
     
    return res;
    
 }

This code not shows TLE.

vector<vector<int>> threeSum(vector<int>& nums) {
    vector<vector<int>> res;
    sort(nums.begin(),nums.end());
    for(int i=0 ; i < nums.size() - 2; ++i){
        if(i > 0 && nums[i-1] == nums[i]) continue;
        int left = i + 1;
        int right = nums.size()-1;
        int target = -nums[i];

        while(left < right){
            int sum = nums[left] + nums[right];
            if(sum < target){
                left++;
            }
            else if(sum > target){
                right--;
            }
            else{
                res.push_back({-target,nums[left],nums[right]});
                while(left < right && res.back()[1] == nums[left]) left++;
                while(left < right && res.back()[2] == nums[right]) right--;
            }
        }
    }

    return res;

}

why ??

#2

hi @khushmanglani31217_7de9bf16f9c8f286 u r returning res and copying back to res in main function again and again thats why
try this – https://ide.codingblocks.com/s/667656

#3

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