Codeforces Round #790 (Div. 4) 1676 E. Eating Queries Solution

 Problem Link:  https://codeforces.com/contest/1676/problem/E

Solution in C++: 

///La ilaha illellahu muhammadur rasulullah

///******Bismillahir-Rahmanir-Rahim******///

///Abul Hasnat  Tonmoy

///Department of CSE,23rd batch

///Islamic University,Bangladesh

///**********ALLAH IS ALMIGHTY************///

#include <bits/stdc++.h>

using namespace std;

int main ()

{

    int t,n,q,x,i,j,s,ss;

    cin>>t;

    while(t--)

    {

        s=ss=0;

        cin>>n>>q;

        int a[n+9];

        for(i=0;i<n;i++)

        {

            cin>>a[i];

            ss+=a[i];

        }

        sort(a,a+n);

        vector<int>v;

        for(i=n-1;i>=0;i--)

        {

            s+=a[i];

            v.push_back(s);

        }

        for(i=0;i<q;i++)

        {

            cin>>x;

            if(x>s)

            cout<<"-1"<<endl;

            else

            {

                cout<<lower_bound(v.begin(),v.end(),x)-v.begin()+1<<endl;

            }

        }

    }

}