POJ 3083 Children of the Candy Corn

  1 #include<iostream>
  2 #include<stdio.h>
  3 #include<cstring>
  4 #include<iomanip>
  5 #include<queue>
  6 #include<algorithm>
  7 using namespace std;
  8 struct node
  9 {
 10     int w;
 11     int e;
 12     int step;
 13 };
 14 int n,m;
 15 int vist[50][50];
 16 int r[4][2]= {{0,-1},{1,0},{0,1},{-1,0}};
 17 int l[4][2]= {{0,1},{1,0},{0,-1},{-1,0}};
 18 int dir[4][2]={{0,1},{-1,0},{1,0},{0,-1}};
 19 char map[50][50];
 20 int sx,sy,ex,ey,ans;
 21 int dfs1(int x,int y,int step)
 22 {
 23     if(x==ex&&y==ey)
 24         return step+1;
 25     if(x<0||x>=n||y<0||y>=m||map[x][y]==‘#‘)
 26         return 0;
 27     ans=(ans+3)%4;
 28     int temp=0;
 29     while(1)
 30     {
 31         temp=dfs1(x+l[ans][0],y+l[ans][1],step+1);
 32         if(temp!=0)
 33             break;
 34         ans=(ans+1)%4;
 35     }
 36     return temp;
 37 }
 38 int dfs2(int x,int y,int step)
 39 {
 40     if(x==ex&&y==ey)
 41         return step+1;
 42     if(x<0||x>=n||y<0||y>=m||map[x][y]==‘#‘)
 43         return 0;
 44     ans=(ans+3)%4;
 45     int temp=0;
 46     while(1)
 47     {
 48         temp=dfs2(x+r[ans][0],y+r[ans][1],step+1);
 49         if(temp!=0)
 50             break;
 51         ans=(ans+1)%4;
 52     }
 53     return temp;
 54 }
 55 int bfs()
 56 {
 57     memset(vist,0,sizeof(vist));
 58     int i,x,y;
 59     struct node p;
 60     queue<struct node>Q;
 61     p.w=sx;
 62     p.e=sy;
 63     p.step=1;
 64     Q.push(p);
 65     vist[sx][sy]=1;
 66     while(!Q.empty())
 67     {
 68         p=Q.front();
 69         Q.pop();
 70         if(p.w==ex&&p.e==ey)
 71             return p.step;
 72         for(i=0;i<4;i++)
 73         {
 74             x=p.w+dir[i][0];
 75             y=p.e+dir[i][1];
 76             if(x>=0&&x<n&&y>=0&&y<m&&map[x][y]!=‘#‘&&vist[x][y]==0)
 77             {
 78                 vist[x][y]=1;
 79                 struct node t;
 80                 t.w=x;
 81                 t.e=y;
 82                 t.step=p.step+1;
 83                 Q.push(t);
 84             }
 85         }
 86     }
 87 }
 88 int main()
 89 {
 90     int T;
 91     scanf("%d",&T);
 92     while(T--)
 93     {
 94         scanf("%d%d",&m,&n);
 95         getchar();
 96         for(int i=0; i<n; i++)
 97         {
 98             for(int j=0; j<m; j++)
 99             {
100                 scanf("%c",&map[i][j]);
101                 if(map[i][j]==‘S‘)
102                 {
103                     sx=i;
104                     sy=j;
105                 }
106                 if(map[i][j]==‘E‘)
107                 {
108                     ex=i;
109                     ey=j;
110                 }
111             }
112             getchar();
113         }
114         ans=0;
115         printf("%d ",dfs1(sx,sy,0));
116         ans=0;
117         printf("%d ",dfs2(sx,sy,0));
118         printf("%d\n",bfs());
119     }
120     return 0;
121 }