OpenJudge

1065:Fractal

总时间限制:
1000ms
内存限制:
65536kB
描述
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.
输入
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.
输出
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.
样例输入
1
2
3
4
-1
样例输出
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
-
来源
Shanghai 2004 Preliminary
全局题号
1085
添加于
2012-09-05
提交次数
1
尝试人数
1
通过人数
0