#include <bits/stdc++.h> using namespace std; int arr[100005]; int q[100005]; int main(){ int n,m,l,r; cin>>n>>m; for (int i = 1;i<=n;i++) { cin>>arr[i]; q[i] = q[i-1] + arr[i]; } for (int j = 1;j<=m;j++){ cin>>l>>r; cout<<q[r]-q[l-1]<<endl; } return 0; }