【POJ 2044】 Weather Forecast

【题目链接】

            http://poj.org/problem?id=2044

【算法】

           广度优先搜索

【代码】

           

#include <algorithm>  
#include <bitset>  
#include <cctype>  
#include <cerrno>  
#include <clocale>  
#include <cmath>  
#include <complex>  
#include <cstdio>  
#include <cstdlib>  
#include <cstring>  
#include <ctime>  
#include <deque>  
#include <exception>  
#include <fstream>  
#include <functional>  
#include <limits>  
#include <list>  
#include <map>  
#include <iomanip>  
#include <ios>  
#include <iosfwd>  
#include <iostream>  
#include <istream>  
#include <ostream>  
#include <queue>  
#include <set>  
#include <sstream>  
#include <stdexcept>  
#include <streambuf>  
#include <string>  
#include <utility>  
#include <vector>  
#include <cwchar>  
#include <cwctype>  
#include <stack>  
#include <limits.h> 
using namespace std;
#define MAXN 400
const int dx[9] = {0,-1,-2,0,0,1,2,0,0};
const int dy[9] = {0,0,0,-1,-2,0,0,1,2};

int i,j,k,n;
int a[MAXN][5][5];
bool visited[5][5][MAXN][7][7][7][7];

struct info
{
        int x,y,day;
        int s1,s2,s3,s4;        
};
inline bool check(int x,int y,int day,int s1,int s2,int s3,int s4)
{
        if (x <= 0 || x > 3 || y <= 0 || y > 3) return false;
        if (a[day][x][y] == 1) return false;
        if (a[day][x][y+1] == 1) return false;
        if (a[day][x+1][y] == 1) return false;
        if (a[day][x+1][y+1] == 1) return false;
        if (s1 >= 7 || s2 >= 7 || s3 >= 7 || s4 >= 7) return false;
        return true;        
}
inline bool bfs()
{
        int i,sa,sb,sc,sd,tx,ty;
        queue< info > q;
        info cur;
        if (a[1][2][2] || a[1][2][3] || a[1][3][2] || a[1][3][3]) return false; 
        memset(visited,false,sizeof(visited));
        while (!q.empty()) q.pop();        
        q.push((info){2,2,1,1,1,1,1});
        visited[2][2][1][1][1][1][1] = true;
        while (!q.empty()) 
        {
                cur = q.front();
                q.pop();
                if (cur.day == n) return true;
                for (i = 0; i < 9; i++)
                {
                        tx = cur.x + dx[i];
                        ty = cur.y + dy[i];
                        sa = cur.s1 + 1;
                        sb = cur.s2 + 1;
                        sc = cur.s3 + 1;
                        sd = cur.s4 + 1;
                        if (tx == 1 && ty == 1) sa = 0;
                        if (tx == 1 && ty == 3) sb = 0;
                        if (tx == 3 && ty == 1) sc = 0;
                        if (tx == 3 && ty == 3) sd = 0;
                        if (check(tx,ty,cur.day+1,sa,sb,sc,sd) && !visited[tx][ty][cur.day+1][sa][sb][sc][sd])
                        {
                                q.push((info){tx,ty,cur.day+1,sa,sb,sc,sd});
                                visited[tx][ty][cur.day+1][sa][sb][sc][sd] = true;
                        }
                }
        }
        return false;
}

int main() 
{
        
        while (scanf("%d",&n) != EOF && n)
        {
                for (i = 1; i <= n; i++)
                {
                        for (j = 1; j <= 4; j++)
                        {
                                for (k = 1; k <= 4; k++)
                                {
                                        scanf("%d",&a[i][j][k]);
                                }
                        }        
                }        
                if (bfs()) printf("%d
",1);
                else printf("%d
",0);
        }
        
        return 0;
    
}