Matrix is a magic square or not

Posted on Apr 26, 2020

C program to check whether matrix is magic square or not.

A Magic Square is a n x n square matrix of distinct element from 1 to n² where sum of any row, column or diagonal is always equal to same number.

Program

#include<stdio.h>
#include<conio.h>
#define MAX 10

void read_matrix(int mat[MAX][MAX], int row, int col)
{
    int i, j;
    for(i=0;i<row;i++)
    {
        for(j=0;j<col;j++)
        {
            printf("Element [%d][%d]\t:",i,j);
            scanf("%d",&mat[i][j]);
        }
    }
}

void print_matrix(int mat[MAX][MAX], int row, int col)
{
    int i, j;
    for(i=0;i<row;i++)
    {
        for(j=0;j<col;j++)
        {
            printf("%d\t",mat[i][j]);
        }
        printf("\n");
    }
}

int magic_square(int mat[MAX][MAX], int row)
{
    int i, j, diag_sum, diag_sum1, row_sum, col_sum;

    diag_sum = 0;
    for(i=0;i<row;i++)
    {
        diag_sum = diag_sum + mat[i][i];
    }

    diag_sum1 = 0;
    for(i=0;i<row;i++)
    {
        diag_sum1 = diag_sum1 + mat[i][row-i-1];
    }

    if(diag_sum != diag_sum1)
        return (0);

    for(i=0;i<row;i++)
    {
        row_sum = 0;
        for(j=0;j<row;j++)
        {
            row_sum = row_sum + mat[i][j];
        }
        if(row_sum != diag_sum)
            return(0);
    }

    for(i=0;i<row;i++)
    {
        col_sum = 0;
        for(j=0;j<row;j++)
        {
            col_sum = col_sum + mat[j][i];
        }
        if(col_sum != diag_sum)
            return(0);
    }

    return(1);
}

void main()
{
    int mat[MAX][MAX];
    int row, col;

    printf("Enter the number of rows or columns of the square matrix\t:");
    scanf("%d",&row);
    col = row;

    printf("Enter the elements of the matrix\n");
    read_matrix(mat, row, col);

    printf("\nMatrix entered is\n");
    print_matrix(mat, row, col);

    if(magic_square(mat, row))
        printf("\nMatrix is magic square");
    else
        printf("\nMatrix is not a magic square");

    getch();
}

Output

********** Run1 ********** 

Enter the number of rows or columns of the square matrix        :3
Enter the elements of the matrix
Element [0][0]  :2
Element [0][1]  :7
Element [0][2]  :6
Element [1][0]  :9
Element [1][1]  :5
Element [1][2]  :1
Element [2][0]  :4
Element [2][1]  :3
Element [2][2]  :8

Matrix entered is
2       7       6
9       5       1
4       3       8

Matrix is magic square


********** Run2 ********** 

Enter the number of rows or columns of the square matrix        :3
Enter the elements of the matrix
Element [0][0]  :1
Element [0][1]  :2
Element [0][2]  :2
Element [1][0]  :2
Element [1][1]  :2
Element [1][2]  :1
Element [2][0]  :2
Element [2][1]  :1
Element [2][2]  :2

Matrix entered is
1       2       2
2       2       1
2       1       2

Matrix is not a magic square