#include <iostream>
using namespace std;

int main() {
	// your code goes here
	int n , q;
	cin>>n;
	cin>>q;
	int arr[n];
	for(int i = 0 ; i< n ; i++){
		cin>> arr[i];
	}
	int p[n];
	p[0] = arr[0];
	for(int i = 1; i<n ; i++){
		p[i] = p[i-1] + arr[i];
	}
	while(q--){
		int l , r;
		cin>>l>>r;
		int sum = 0;
		if(l==0){
			sum = p[r];
		}
		else {
			sum = p[r] + p[l-1];
		}
		cout<<sum<<endl;
	}
	return 0;
}