题解 | #多组_二维数组_T组形式#

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 count3 = in.nextInt();

        for (int k = 0; k < count3; k++) {
            int count1 =in.nextInt();
            Long sum = 0L;
            int count2 = in.nextInt();
            for (int i = 0; i < count1; i++) {
                for (int j = 0; j < count2; j++) {
                    sum += in.nextInt();
                }

            }
            System.out.println(sum);
        }


    }
}