[POJ2083] Fracal

Description

A fractal is an object or quantity that displays self-similarity, in a somewhat technical sense, on all scales. The object need not exhibit exactly the same structure at all scales, but the same "type" of structures must appear on all scales. 
A box fractal is defined as below :

• A box fractal of degree 1 is simply 
  X
• A box fractal of degree 2 is 
  X X 
  X 
  X X
• If using B(n - 1) to represent the box fractal of degree n - 1, then a box fractal of degree n is defined recursively as following 

  B(n - 1)        B(n - 1)
  
          B(n - 1)
  
  B(n - 1)        B(n - 1)

Your task is to draw a box fractal of degree n.

Input

The input consists of several test cases. Each line of the input contains a positive integer n which is no greater than 7. The last line of input is a negative integer −1 indicating the end of input.

Output

For each test case, output the box fractal using the 'X' notation. Please notice that 'X' is an uppercase letter. Print a line with only a single dash after each test case.

Sample Input

1
2
3
4
-1

Sample Output

X
-
X X
 X
X X
-
X X   X X
 X     X
X X   X X
   X X
    X
   X X
X X   X X
 X     X
X X   X X
-
X X   X X         X X   X X
 X     X           X     X
X X   X X         X X   X X
   X X               X X
    X                 X
   X X               X X
X X   X X         X X   X X
 X     X           X     X
X X   X X         X X   X X
         X X   X X
          X     X
         X X   X X
            X X
             X
            X X
         X X   X X
          X     X
         X X   X X
X X   X X         X X   X X
 X     X           X     X
X X   X X         X X   X X
   X X               X X
    X                 X
   X X               X X
X X   X X         X X   X X
 X     X           X     X
X X   X X         X X   X X
-
解析
一道比较简单的分形图，n<=7,则边长最大为739，开一个800*800的数组记录当前是“X”还是“ ”，当他处于第n级时，如果需要向n-1级递归，就有五个方向：
左上角，右上角，中间，左下角，右下角。

#include<cstring>
#include<cstdio>
#include<cmath>
using namespace std;
int n;
bool maps[][];
inline void dfs(int m,int bian,int xx,int yy)
{
    if(m==){
        maps[xx][yy]=;
        return;
    }
    dfs(m-,bian/,xx-bian/,yy-bian/);
    dfs(m-,bian/,xx-bian/,yy+bian/);
    dfs(m-,bian/,xx+bian/,yy-bian/);
    dfs(m-,bian/,xx+bian/,yy+bian/);
    dfs(m-,bian/,xx,yy);
}
int main()
{
    while()
    {
        memset(maps,,sizeof maps);
        scanf("%d",&n);
        if(n==-)break;
        int bian=;
        for(int i=;i<=n-;i++) bian*=;
        dfs(n,bian,(bian+)/,(bian+)/);//分别传入第n级，边长（长 和 高相等），中心位置的横纵坐标
        for(register int i=;i<=bian;i++)
        {
            for(register int j=;j<=bian;j++)
            {
                if(maps[i][j])printf("X");
                 else printf(" ");
             }
            printf("\n");
        }
        printf("-\n");
    }
}