#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 1e6 + 10, INF = 0x3f3f3f3f, MOD = 1E9 + 7;
ll n, m, a[N], ans;
int main(int argc, char* argv[]) {
    cin >> n >> m;
    for (int i = 1; i <= n; i++)
        cin >> a[i];

    for (int i = 1; i <= n; i++)
        a[i] += a[i - 1];
    while (m--) {
        int l, r;
        cin >> l >> r;
        if (l > r)
            swap(l, r);
        cout << a[r] - a[l - 1] << endl;
    }

    return 0;
}