Magic.java

import java.util.*;

public class Magic {

    public static void makeSquare(int n, int[][] anArray){

        int total, middle, start, end, currentX, currentY, i, j, k;
        total = n * n;
        middle = ((n + 1) / 2) - 1;
        start = 0;
        end = n - 1;
        currentX = start;
        currentY = middle;

        for (i = 1; i < total + 1; i++){
            int a, b;
            anArray[currentX][currentY] = i;

            if (currentX == 0 && currentY == end){
                currentX = currentX + 1;
            }
            else if (currentX == 0) {
                a = end;
                b = currentY + 1;
                if (anArray[a][b] != 0){
                    currentX = currentX + 1;
                } else {
                    currentX = a;
                    currentY = b;
                }
            }
            else if (currentY == end){
                a = currentX - 1;
                b = start;
                if (anArray[a][b] != 0){
                    currentX = currentX + 1;
                } else {
                    currentX = a;
                    currentY = b;
                }
            } else {
                a = currentX - 1;
                b = currentY + 1;
                if (anArray[a][b] != 0){
                    currentX = currentX + 1;
                } else {
                    currentX = a;
                    currentY = b;
                }
            }
        }
        for (j = 0; j < end + 1; j++){
            for (k = 0; k < end + 1; k++){
                System.out.print(anArray[j][k]);
                if (k < end){
                    System.out.print(" ");
                }
            }
            if (j < end){
                System.out.println("");
            }
        }
    }
    public static void main(String[] args) {
        Scanner myScanner = new Scanner(System.in);

        int check;
        check = myScanner.nextInt();

        int[][] anArray;
        anArray = new int[check][check];

        makeSquare(check, anArray);
    }
}