#include <iostream>

using namespace std;

int n, q, a[int(1e5+3)];
int64_t ps[int(1e5+3)], ans;
int l, r;

int main()
{   
    cin.tie(0) -> sync_with_stdio(0);

    cin >> n >> q;
    for(int i=1; i<=n; ++i){
        cin >> a[i];
        ps[i] = ps[i-1] + a[i];
    }
    while(q--){
        cin >> l >> r;
        ans = 0;
        for(int i=l; i<=r; ++i)
            ans += a[i]*(ps[i-1]-ps[l-1]);
        cout << ans << '\n';
    }

    return 0;
}