#include<bits/stdc++.h>
using namespace std;
int n,a[110],q,x,y,s[110];
int main(){
	cin>>n;
    cin>>q;
	for(int i=1;i<=n;i++){
		cin>>a[i];
		s[i]=s[i-1]+a[i];
	}
	
	while(q--){
		cin>>x>>y;
		cout<<s[y]-s[x-1]<<endl;	
	} 
}