#include<bits/stdc++.h>
using namespace std;

int main(){
    int N,Q;
    cin >> N >> Q;
    int A[N],Prefix[N];
    for (int i=0; i<N; i++){
        cin >> A[i];
        Prefix[0] = A[0];
        Prefix[i] = Prefix[i-1] + A[i];
    }
    for (int x =0 ; x<Q; x++){
        int i,j,Sum[Q];
        cin >> i >> j;
        Sum[i] = Prefix[j] - Prefix[i-1];
        cout << Sum[i] << endl;
    }
    return 0;
}