#include <bits/stdc++.h>
using namespace std;
#pragma GCC target ("avx2")
#pragma GCC optimization ("O3")
#pragma GCC optimization ("unroll-loops")

int main() {
    // ios_base::sync_with_stdio(0);
    // cin.tie(NULL);
    freopen("rsq.in", "r", stdin);
    freopen("rsq.out", "w", stdout);
    int n, m, temp;
    cin >> n >> m;
    vector<int> arr(n+1, 0);
    for(int i = 1; i <= n; i++) {
        cin >> temp;
        arr[i] = arr[i-1] + temp;
        // cout << "temp is " << temp << "\narr[i] is " << arr[i] << "\ni is " << i << "\n\n";
    }
    int l, r;
    for(int i = 0; i < m; i++) {
        cin >> l >> r;
        // cout << i << "\n";
        // cout << arr[l] << "\t\t" << arr[r] << "\n\n";
        cout << arr[r] - arr[l-1] << "\n";
    }
    return 0;
}