题解 | #单组_二维数组#

import java.util.Scanner;

// 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) {
        Scanner in = new Scanner(System.in);
        
        int row = in.nextInt();
        int col = in.nextInt();

        long sum = 0;

        for(int i = 0;i < row;i++){
            for(int j = 0;j < col;j++){
                sum += in.nextInt();
            }
        }
        System.out.println(sum);
    }
}