#include <bits/stdc++.h>
using namespace std;
int a[100010], b[100010], n, q, l, r;
int main() {
cin >> n >> q;
for (int i = 1; i <= n; i++) {
cin >> a[i];
b[i] = b[i - 1] + a[i];
}
for (int i = 1; i <= q; i++) {
cin >> l >> r;
cout << b[r] - b[l - 1] << endl;
}
return 0;
}