#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;
}

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

NCAzCjEgMiAzIDQKMSAyCjEgMwoyIDMK

4 3
1 2 3 4
1 2
1 3
2 3