Java 如何找出在矩阵中输入的整数是否使其成为幻方？

我需要使用多种方法来确定用户输入的矩阵中的数字是否为幻方，即所有行、列和对角线的和是否相等。由于某种原因，我无法在第二种方法中计算出如何将每个对角线的总和相加并相互比较。我还需要想出一种方法来找到每一行的总和，并将它们相互比较以获得等价性。然后，我需要创建另一个方法，就像一个包含行的方法一样，除了包含列

/**
 * all rows, columns, and diagonals = the same sum
 *
 * @author Jenny Nguyen
 * @version 5-6-19
 */
import java.util.Scanner;
public class MagicSquare
{
    public static void main (String [] args)
    {
        //Declare + initialize
        Scanner input = new Scanner(System.in);
        int size;

        //asks user how big square will be
        System.out.println("How many rows and columns will there be in the square?");
        size = input.nextInt();
        int[][] matrix = new int[size][size];
        //calls up method
        read2D(matrix, input);
        System.out.println("The square looks like this: ");
        //pritns matrix
        for (int row=0; row<matrix.length; row++)
        {
            for (int col=0; col< matrix[row].length; col++)
            {
                System.out.print (matrix[row][col] + "\t"); //print the item
            }
            System.out.println(); //go to next line for next row
        }
        //calls up other method

        //prints if it's a magic square or not
        if (diagonals(matrix, size) == false)
            System.out.println("This is not a magic square.");
        else if (diagonals(matrix,size) == true) //if method compare(matric) == true
            System.out.println("This is a magic square.");
        else
            System.out.println("try again");
        //program needs to work for square of any size and values
    }
    //Method 1
    /**
     * asks user to enter numbers in the square
     *
     * @param int[][]  
     * @return    none
     */
    public static void read2D(int [][]  matrix, Scanner input)
    {
        for (int row=0; row<matrix.length; row++)
        {
            for (int col=0; col< matrix[row].length; col++)
            {
                System.out.print ("Please enter an integer: "); //prompt user
                matrix[row][col] = input.nextInt();
            }
        }
    }
    //Method 2
    /**
     * determine whether diagonals are equal or not
     *
     * @param int[][] matrix, int size
     * @return    none
     */
    public static boolean diagonals(int [][]  matrix, int size)
    {
        int dia1=0;
        for (int i=0, j=0; i<size && j<size; i++, j++) 
        {
            //adds diagonal integers left to right
            dia1 += matrix[i][j];
        }
        int dia2=0;
        for (int i=0,j=size-1 ; i<size && j>=0 ; i++, j--)
        {
            //adds diagonal integers right to left
            dia2 += matrix[i][j];
        }
        if (dia1==dia2)
            return true;
        else
            return false;
    }
}

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正方形中的主对角线：行的索引等于列的索引

平方次对角线：行和列索引之和等于矩阵大小

以下是矩阵中的methodworks，其中rows==cols：

public void diagonalsSum(int[][] matrix, int size) {
        int primaryDiagonalSum = 0;
        int secondaryDiagonalSum = 0;
        if (rows == cols) {
            for (int i = 0; i < size; i++) {
                for (int j = 0; j < size; j++) {
                    if (i == j) {
                        primaryDiagonalSum += matrix[i][j];
                    }
                    if (i + j == size) {
                        secondaryDiagonalSum += matrix[i][j];
                    }
                }
            }
        }
        System.out.println("Primary diagonal sum = " + primaryDiagonalSum);
        System.out.println("Secondary diagonal sum = " + secondaryDiagonalSum);
}

下面是每行总和的方法，根据您的需要调整代码，并将每行与另一行进行比较

public void sumOfRows(int[][] matrix, int size) {
        int[] rowsSum = new int[size];
        for (int i = 0; i < size; i++) {
            for (int j = 0; j < size; j++) {
                rowsSum[i] += matrix[i][j];
            }
        }
        int i = 1;
        for (int sum : rowsSum) {
            System.out.println("Sum of row " + (i++) + " = " + sum);
        }
}

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你有什么问题？问题是什么？我想知道我的第二种方法对角线的问题。以及如何计算行和行之间的比较非常感谢，我将检查它！