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);
        // 注意 hasNext 和 hasNextLine 的区别


        int row = in.nextInt();
        int col = in.nextInt();
        long num = 0;
        for (int i = 0; i < row; i++) {
            if (in.hasNextLine()) {
                for (int j = 0; j < col; j++) {
                    if (in.hasNext()) {
                        num += in.nextInt();
                    }
                }
            }

            
        }
        System.out.println(num);
    }
}