#include <bits/stdc++.h>
#define int long long
using namespace std;
const int INF = 0x3f3f3f3f;
const int N = 1e6 + 10;
int n , m , x , l , r;
int a [N];
signed main()
{

	    cin >> n >> m;
	    for(int i = 1; i <= n; i++)
		{
		    cin >> x;
		    a [i] = a [i - 1] + x;
	    }
	    for(int i = 1; i <= m; i++)
		{
		    cin >> l >> r;
		    cout << a [r] - a [l - 1] << "\n";
	    }
		return 0;
}