poj 2083 Fractal 【递归打印字符】

Fractal

Time Limit: 1000MS Memory Limit: 30000KTotal Submissions: 8356 Accepted: 3972

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

1234-1

Sample Output

X-X X XX X-X X   X X X     XX X   X X   X X    X   X XX X   X X X     XX X   X X-X X   X X         X X   X X X     X           X     XX X   X X         X X   X X   X X               X X    X                 X   X X               X XX X   X X         X X   X X X     X           X     XX X   X X         X X   X X         X X   X X          X     X         X X   X X            X X             X            X X         X X   X X          X     X         X X   X XX X   X X         X X   X X X     X           X     XX X   X X         X X   X X   X X               X X    X                 X   X X               X XX X   X X         X X   X X X     X           X     XX X   X X         X X   X X-

题意：打印字符，很有意思的题目吧。

思路：先填满空格，最后递归打印就好了。

写的代码有点渣。。。

AC代码：

#include <cstdio>#include <cstring>#include <cmath>#include <cstdlib>#include <algorithm>#include <queue>#include <stack>#include <map>#include <set>#include <vector>#define INF 0x3f3f3f#define eps 1e-8#define MAXN (2000+10)#define MAXM (100000)#define Ri(a) scanf("%d", &a)#define Rl(a) scanf("%lld", &a)#define Rf(a) scanf("%lf", &a)#define Rs(a) scanf("%s", a)#define Pi(a) printf("%d\n", (a))#define Pf(a) printf("%.2lf\n", (a))#define Pl(a) printf("%lld\n", (a))#define Ps(a) printf("%s\n", (a))#define W(a) while(a--)#define CLR(a, b) memset(a, (b), sizeof(a))#define MOD 1000000007#define LL long long#define lson o<<1, l, mid#define rson o<<1|1, mid+1, r#define ll o<<1#define rr o<<1|1using namespace std;char str[MAXN][MAXN];int Pow(int a, int b){    int ans = 1;    while(b--)        ans *= a;    return ans;}void getmap(int r1, int c1, int r2, int c2, int n)//在左上角(r1, c1) 右下角(r2, c2)的矩形区域内打印字符{    if(n == 1)    {        str[r1][c1] = 'X';        return ;    }    int op = Pow(3, n-2);    getmap(r1, c1, r1+op-1, c1+op-1, n-1); getmap(r1, c1+op-1+op+1, r1+op-1, c1+op-1+op+1+op-1, n-1);    getmap(r1+op, c1+op, r1+op+op-1, c1+op+op-1, n-1);    getmap(r1+op-1+op+1, c1, r1+op-1+op+1+op-1, c1+op-1, n-1); getmap(r1+op+op, c1+op+op, r1+op+op+op-1, c1+op+op+op-1, n-1);}int main(){    int n;    while( Ri(n), n != -1)    {        int M = Pow(3, n-1);        CLR(str, 0);        for(int i = 0; i < M; i++)            for(int j = 0; j < M; j++)                str[i][j] = ' ';        getmap(0, 0, M-1, M-1, n);        for(int i = 0; i < M; i++)            printf("%s\n", str[i]);        printf("-\n");    }    return 0;}