poj 2083

一行一行的输出比一个字符一个字符的输出快了10倍

#include <iostream>
#include <cstdio>
#include <iomanip>
#include <string>
#include <cstdlib>
#include <cstring>
#include <queue>
#include <set>
#include <vector>
#include <map>
#include <algorithm>
#include <cmath>
#include <stack>

#define INF 0x3f3f3f3f
#define LINF 0x3f3f3f3f3f3f3f3f
#define ll long long
#define ull unsigned long long
#define uint unsigned int

using namespace std;

template<typename T>
T fpow(T a, T b) {
	T ans = 1;
	while (b) {
		if (b & 1)ans *= a;
		b >>= 1;
		a *= a;
	}
	return ans;
}

char ans[750][750];
int n,len;

void dfs(int now, int x, int y) {
	if (now == 1) {
		ans[x][y] = 'X';
		return;
	}

	int s = fpow(3, now - 2);
	dfs(now - 1, x, y);
	dfs(now - 1, x, y + s * 2);
	dfs(now - 1, x + s, y + s);
	dfs(now - 1, x + s * 2, y);
	dfs(now - 1, x + s * 2, y + s * 2);
}

int main() {
	while (scanf("%d", &n), n != -1) {
		memset(ans, ' ', sizeof(ans));
		len = fpow(3, n - 1);
		dfs(n, 0, 0);
		for (int i = 0; i < len; i++)
			ans[i][len + 1] = '\0';
		for (int i = 0; i < len; i++) 
			printf("%s\n", ans[i]);
		printf("-\n");
	}
	
	return 0;
}