#include <iostream>
#include <vector>
#include <algorithm>
#include <set>
#include <cmath>
#include <map>
#include <cstring>
using namespace std;
vector<long long> prefix_sum;

long long query(int a, int b) {
    if(a == 0) {
        return prefix_sum[b];
    }
    return prefix_sum[b] - prefix_sum[a - 1];
}
int main() {
    int n, q;
    cin >> n >> q;

    vector<int> v(n);
    long long sum = 0;
    for(int i = 0; i < n; i++) {
        cin >> v[i];
        sum += v[i];
        prefix_sum.push_back(sum);
    }


    for(int i = 0; i < q; i++) {
        int a, b;
        cin >> a >> b;
        a--;
        b--;

        cout << query(a, b) << endl;

    }

    return 0;
}