题解 | 单组_二维数组

import java.util.Scanner;
import java.io.*;
import java.util.*;
// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) throws IOException{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st = new StringTokenizer(br.readLine());
        int n = Integer.parseInt(st.nextToken());
        int m = Integer.parseInt(st.nextToken());
        long sum = 0;
        for(int i = 0 ; i < n ; i++)
        {
            st = new StringTokenizer(br.readLine());
            for(int j = 0 ; j < m ; j++)
            {
                sum += Long.parseLong(st.nextToken());
            }
        }
        System.out.print(sum);
    }
}