前缀和_java

import java.util.*;

public class Main{
    private static int N=100010;
    private static int[] res=new int[N];
    
    public static void main(String[] args){
        Scanner in=new Scanner(System.in);
        int n=in.nextInt();
        int m=in.nextInt();
        for(int i=1;i<=n;i++){
            res[i]=res[i-1]+in.nextInt();
        }
        while(m-->0){
            int i=in.nextInt();
            int j=in.nextInt();
            System.out.println(res[j]-res[i-1]);
        }
    }
}