poj 1573 Robot Motion

一道简单的模拟题:

#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<algorithm>
#include<cmath>
#include<queue>
#include<set>
#include<vector>
using namespace std;
int judge( char map[][124], int visit[][124],int x ,int y ,int n , int m)
{ 
     if( x <1 || x >n || y < 1 || y > m )  return 2;
     if( visit[x][y]!=0 ) return 1;  
      return 0;
}
void DFS( char map[][124],int visit[][124],int n , int m , int x,int y )
{
    int t;
//    printf( "%c %d %d\n",map[x][y],x,y );
    switch( map[x][y] )
    {
       case 'S': t = judge( map , visit, x+1 ,y ,n ,m );
               if( t!=0 )
                {
                    if( t == 1 )
                    printf( "%d step(s) before a loop of %d step(s)\n",visit[x+1][y]-1,visit[x][y]+1-visit[x+1][y]  );
                    else printf( "%d step(s) to exit\n",visit[x][y] ); 
                }
                else 
                {
                    visit[x+1][y] = visit[x][y] + 1; 
                    DFS( map ,visit, n , m , x+ 1,y );
                }
                break;
      case 'N':t = judge( map , visit,  x-1 ,y , n, m );
                if( t!=0 )
                {
                    if( t == 1 )
                    printf( "%d step(s) before a loop of %d step(s)\n",visit[x-1][y]-1,visit[x][y] +1-visit[x-1][y]  );
                    else printf( "%d step(s) to exit\n",visit[x][y] );        
                } 
                else 
                {
                    visit[x-1][y] = visit[x][y] + 1;
                    DFS( map ,visit, n , m , x - 1,y );
                    
                }
                break;    
      case 'E': t= judge(  map , visit, x ,y+1 ,n,m);
               if( t!=0 )
                {
                if( t == 1 )
                    printf( "%d step(s) before a loop of %d step(s)\n",visit[x][y+1]-1,visit[x][y]+1 -visit[x][y+1]  );
                    else printf( "%d step(s) to exit\n",visit[x][y]  ); 
                }
                else
                {
                    visit[x][y+1] = visit[x][y] + 1;
                    DFS( map ,visit, n , m , x ,y + 1 );
                }
                break;    
      case 'W': t = judge( map , visit,  x ,y -1 ,n,m);
                if( t!=0 )
                {
                    if( t == 1 )
                    printf( "%d step(s) before a loop of %d step(s)\n",visit[x][y-1]-1,visit[x][y]+1-visit[x][y-1]  );
                    else printf( "%d step(s) to exit\n",visit[x][y]  );   
                }
                else 
                {
                    visit[x][y-1] = visit[x][y] + 1;
                    DFS( map ,visit, n , m , x ,y - 1 );
                }
                break;        
    }    
}
int main(  )
{
    char map[124][124];
    int n , m ,start;
    while( scanf( "%d %d %d",&n,&m,&start ),n||m||start )
    { 
        int visit[124][124] = {0};
        for( int i = 1 ; i <= n ; i ++ )
        {
            scanf( "%s",map[i] + 1 );    
        }
        visit[1][start] = 1;
        DFS( map ,visit, n , m , 1,start );
    }  
    //system( "pause" );
    return 0;
}