#include<bits/stdc++.h>
using namespace std;
int a[100010],b[100010],c[100010],d[100010];
int main(){
int n,q;
cin>>n>>q;
for(int i=1;i<=n;i++){
cin>>a[i];
d[i]=a[i]+d[i-1];
}
for(int i=1;i<=q;i++){
cin>>b[i]>>c[i];
cout<<d[c[i]]-d[b[i]-1]<<"\n";
}
return 0;
}