#include <iostream>
using namespace std;

int main() {
    int n, q;
    cin >> n >> q;

    int arr[n];

    for (int i = 0; i < n; i++) {
        cin >> arr[i];
    }

    // Overwrite arr with prefix sums
    for (int i = 1; i < n; i++) {
        arr[i] = arr[i - 1] + arr[i];
    }

    while (q--) {
        int l, r;
        cin >> l >> r;

        int sum;

        if (l == 0) {
            sum = arr[r];
        }
        else {
            sum = arr[r] - arr[l - 1];
        }

        cout << sum << endl;
    }

    return 0;
}