#include <iostream>
using namespace std;
int n,m,l,r,a[100010],b[100010];
int main(){
    cin >> n >> m;
    for (int i = 1;i <= n;i++){
        cin >> a[i];
        b[i] = a[i] + b[i-1];
    }
    for (int i = 1;i <= m;i++){
        cin >> l >> r;
        int ans = b[r];
        for (int i = 1;i < l;i++) ans -= a[i];
        cout << ans << endl;
    }
}