...

#include<bits/stdc++.h>
using namespace std;
int a[1000005];
int p[1000005];
int main(){
int n , q;
cin >> n >> q;
for(int i = 1;i <= n;i++) cin >> a[i] , p[i] = a[i] + p[i-1];
while(q--){
int l , r;
cin >> l >> r;
cout << p[r] - p[l-1] << endl;
}
return 0;
}