Two some code

class Solution {
public:

    struct node{
        int val;
        int indx;
    };


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

        vector<node> v;

        int n = nums.size();

        for(int i = 0; i<n; i++){
            node a;
            a.val = nums[i];
            a.indx = i;
            v.push_back(a);
        }

        sort(v.begin(), v.end(),[](node a, node b){

        return a.val<b.val;

        });


        int i = 0, j = n-1;

        while(i<j){

            if(v[i].val + v[j].val > target)j--;
            else if(v[i].val+v[j].val<target)i++;
            else return{v[i].indx, v[j].indx};

        }

        return {-1,-1};

    }
};