java 代码

import java.io.*;
import java.lang.Integer;
class Main{

    public static void main(String[] args)throws Exception{
        BufferedReader buf = new BufferedReader(new InputStreamReader(System.in));
        String[] str = buf.readLine().split(" ");
        String[] strNums = buf.readLine().split(" ");
        int n = Integer.valueOf(str[0]);
        int k = Integer.valueOf(str[1]);
        int[] nums = new int[n + 1];
        int cnt = 0;
        for(int i = 1; i <= n; ++i){
            cnt += Integer.valueOf(strNums[i - 1]);
            nums[i] = cnt;
        }
        for(int i = 1; i <= k; ++i){
            String[] kn = buf.readLine().split(" ");
            int a = Integer.valueOf(kn[0]);
            int b = Integer.valueOf(kn[1]);
            System.out.println(nums[b] - nums[a - 1]);
        }
    }
}