#include <iostream>

using namespace std;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    int n,m;
    cin >> n >> m;
    int arr[100001];
    int begind;
    int last;
    for (int i =  1;i < n+1;i++ ) {
        int tmp;
        cin >> tmp;
        arr[i] = arr[i-1] + tmp;
    }
    for (int i =  0;i < m;i++) {
        cin >> begind >> last;
        cout << arr[last] - arr[begind-1] << "\n";

    }    return 0;
}