---

#include <iostream>
using namespace std;

int sum(int d[], int a, int b) {
    if (a == 0) return d[b];
    return d[b] - d[a - 1];
}

int main() {
    int a[100000];
    int d[100000];
    int n;
    cin >> n;
    int m;
    cin >> m;
    for (int i = 0; i < n; i++) {
        cin >> a[i];
    }
    d[0] = a[0];
    for (int i = 1; i < n; i++) {
        d[i] = d[i - 1] + a[i];
    }
    for (int i = 0; i < m; i++) {
        int x, y;
        cin >> x >> y;
        cout << sum(d, x - 1, y - 1) << endl;
    }
}