BAEKJOON_11659

import java.io.*;
import java.util.*;

public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader br =new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw =new BufferedWriter(new OutputStreamWriter(System.out));

        StringTokenizer st = new StringTokenizer(br.readLine());

        int N = Integer.parseInt(st.nextToken());
        int M = Integer.parseInt(st.nextToken());

        int[] arr = new int[N+1];
        arr[0] = 0;
        StringTokenizer st2 = new StringTokenizer(br.readLine());
        for(int i=1; i<N+1; i++){
            arr[i] = arr[i-1]+Integer.parseInt(st2.nextToken());
        }
        int sum=0;
        for(int i=0; i<M; i++){
            StringTokenizer st3= new StringTokenizer(br.readLine());
            int a = Integer.parseInt(st3.nextToken());
            int b= Integer.parseInt(st3.nextToken());
            sum =arr[b]-arr[a-1];
            bw.write(String.valueOf(sum));
            bw.newLine();
            bw.flush();
        }
        bw.close();
    }
}