#include<bits/stdc++.h>
using namespace std;
int n,q,x,y,a[200010],s[200010]; 
int main(){
	scanf("%d%d",&n,&q);
	for(int i=1;i<=n;i++){
		scanf("%d",&a[i]);
		s[i]=s[i-1]+a[i];
	}
	for(int i=1;i<=q;i++){
		scanf("%d%d",&x,&y);
		cout<<s[y]-s[x-1]<<"\n";
	} 
	return 0;
}