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 scanner = new Scanner(System.in);
        int t = scanner.nextInt();
        while (t > 0) {
            int n = scanner.nextInt();
            int m = scanner.nextInt();
            long sum = 0L;
            for (int i = 0; i < n; i++) {
                for (int j = 0; j < m; j++) {
                    sum += scanner.nextInt();
                }
            }
            System.out.println(sum);
            t--;
        }
        scanner.close();
    }
}