Envío 6155

Código

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        int n = scanner.nextInt();
        int[][] matrix = new int[n][n];
        int magicNumber = 0;
        boolean flag = true;

        for (int i = 0; i < n; i++) {
            int count = 0;
            for (int j = 0; j < n; j++) {
                matrix[i][j] = scanner.nextInt();
                count += matrix[i][j];
            }
            if (i == 0) {
                magicNumber = count;
            } else {
                if (magicNumber != count) {
                    flag = false;
                }
            }
        }

        if (!flag) {
            System.out.println("No");
        }

        int count1 = 0;
        int count2 = 0;
        for (int i = 0; i < n; i++) {
            int count = 0;
            for (int j = 0; j < n; j++) {
                count += matrix[i][j];
            }
            if (magicNumber != count) {
                System.out.println("No");
                return;
            }
            count1 += matrix[i][i];
            count2 += matrix[i][(n-1)-i];
        }

        if (magicNumber != count1 || magicNumber != count2) {
            System.out.println("No");
            return;
        }

        System.out.println("Yes");
    }
}