Educational Codeforces Round 130 (Rated for Div. 2) 1697B. Promo Solution

Problem Link: https://codeforces.com/contest/1697/problem/B

 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;

long long s[200009],a[200009];

int main()

{

     int n,q,x,y,i;

     cin>>n>>q;

     for(i=1;i<=n;i++)

         cin>>a[i];

     sort(a+1,a+n+1,greater<long long>());

     for(i=1;i<=n;i++)

     {

         s[i]=s[i-1]+a[i];

     }

     while(q--)

     {

         cin>>x>>y;

         cout<<s[x]-s[x-y]<<endl;

     }

}