奇数阶魔方阵

/*************************************************************************
    > File Name: testmain.c
    > Author: KrisChou
    > Mail:zhoujx0219@163.com 
    > Created Time: Sun 17 Aug 2014 10:09:22 PM CST
 ************************************************************************/

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

int main(int argc, char *argv[])
{
    int size;
    int row,col;
    int num = 0;
    int index;
    size = atoi(argv[1]);
    /* 动态分配二维数组，用于存放魔方阵 */
    int **arr = (int**)calloc(size,sizeof(int*));
    for(index = 0; index < size; index++)
    {
        arr[index] = (int*)calloc(size,sizeof(int));
    }
    /* 存放魔方阵 */
    row = 0;
    col = size >> 1;
    arr[row][col] = ++num;
    while(num < size * size)
    {
        if(num % size == 0)
        {
            row = (row + 1) % size;
            col = col;
            arr[row][col] = ++num;
        }else
        {
            row = (row - 1 + size) % size;
            col = (col + 1) % size;
            arr[row][col] = ++num;
        }
    }
    /* 打印 */
    for(row = 0; row < size; row++)
    {
        for(col = 0; col < size; col++)
        {
            printf("%-3d",arr[row][col]);
        }
        printf("\n");
    }
    /* 释放存储空间 */
    for(index = 0; index < size; index++)
    {
        free(arr[index]);
        arr[index] = NULL;
    }
    free(arr);
    arr = NULL;
    
    return 0;
}