#include <stdio.h>
#include <stdlib.h>

int f(int n, int x, int y) {
    return (x + y * 2 + 1) % n;
}

void generateMagicSquare(int n) {
    int i, j;

    if (n < 3 || (n % 2) == 0) {
        printf("Please enter a valid odd number greater than or equal to 3 for the order of the magic square.\n");
        return;
    }

    for (i = 0; i < n; i++) {
        for (j = 0; j < n; j++)
            printf("% 4d", f(n, n - j - 1, i) * n + f(n, j, i) + 1);
        putchar('\n');
    }
    printf("\n Magic Constant: %d.\n", (n * n + 1) / 2 * n);
}

void siameseMethod(int n) {
    int magicSquare[n][n];

    // Initialize all elements of the magic square to 0
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            magicSquare[i][j] = 0;
        }
    }

    int num = 1;
    int row = 0, col = n / 2;

    while (num <= n * n) {
        magicSquare[row][col] = num;

        int next_row = (row - 1 + n) % n;
        int next_col = (col + 1) % n;

        if (magicSquare[next_row][next_col] != 0) {
            row = (row + 1) % n;
        } else {
            row = next_row;
            col = next_col;
        }

        num++;
    }

    // Printing the magic square
    printf("Magic Square of order %d:\n", n);
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            printf("%3d ", magicSquare[i][j]);
        }
        printf("\n");
    }
    printf("\n Magic Constant: %d.\n", (n * n + 1) / 2 * n);
}


// A function to generate odd sized magic squares
void generateSquare(int n)
{
	int magicSquare[n][n];

	// set all as 0
	memset(magicSquare, 0, sizeof(magicSquare));

	// Initialize position for 1
	int i = n / 2;
	int j = n - 1;

	// One by one put all values in magic square
	for (int num = 1; num <= n * n;) {
		if (i == -1 && j == n) // 3rd condition
		{
			j = n - 2;
			i = 0;
		}
		else {
			// 1st condition helper if next number
			// goes to out of square's right side
			if (j == n)
				j = 0;

			// 1st condition helper if next number
			// is goes to out of square's upper side
			if (i < 0)
				i = n - 1;
		}
		if (magicSquare[i][j]) // 2nd condition
		{
			j -= 2;
			i++;
			continue;
		}
		else
			magicSquare[i][j] = num++; // set number

		j++;
		i--; // 1st condition
	}

	// Print magic square
	printf("The Magic Square for n=%d:\nSum of "
		"each row or column %d:\n\n",
		n, n * (n * n + 1) / 2);
	for (i = 0; i < n; i++) {
		for (j = 0; j < n; j++)
			printf("%3d ", magicSquare[i][j]);
		printf("\n");
	}
}


void generateOddMagicSquare(int n) {

    int magicSquare[n][n];
    int num = 1;
    int row = 0, col = n / 2;

    //fill the square, alternatively use memset
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            magicSquare[i][j] = 0;
        }
    }

    while (num <= n * n) {
        magicSquare[row][col] = num;

        int next_row = (row - 1 + n) % n;
        int next_col = (col + 1) % n;

        if (num % n == 0) {
            row = (row + 1) % n;
        } else {
            row = next_row;
            col = next_col;
        }

        num++;
    }

    printf("Magic Square of order %d:\n", n);
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            printf("% 4d", magicSquare[i][j]);
        }
        printf("\n");
    }
    printf("\nMagic Constant: %d\n", (n * n + 1) / 2 * n);
}

int main() {
    int n;

    do {
        printf("Enter an odd number (n >= 3) for the order of the magic square: ");
        scanf("%d", &n);

        if (n < 3 || (n % 2) == 0)
            printf("Please enter an odd number greater than or equal to 3 for the order of the magic square.\n");
    } while (n < 3 || (n % 2) == 0);

    //version one (uses some extra function, study it)
    generateMagicSquare(n);
    printf("\n\n");

    //version two (plain 2d matrix use)
    siameseMethod(n);
    printf("\n\n");

    // version three (very similar)
    // https://www.geeksforgeeks.org/magic-square/
    generateSquare(n);
    printf("\n\n");

    // version four (plain from wikipedia description)
    generateOddMagicSquare(n);
    return 0;
}