pku1376 Robot

第一道A*

 想知道自己的启发函数有没有错的话，把函数返回值设为0再交上去看能不能通过就行了

#include  < iostream >
#include  < vector >
#include  < queue >
using   namespace  std;

#define  MAXN 26001
#define  tile(x,y) ((x-1)*m+y)
#define  tile_x(t) (t/m+1)
#define  tile_y(t) (t%m)
#define  hamilton(s) ((abs(tile_x(s)-tile_x(ed))+abs(tile_y(s)-tile_y(ed)))/3)


int  graph[ 55 ][ 55 ],n,m,g[MAXN],mk[MAXN],st,ed,s,x,y,op,ns,nop,f[MAXN];
char  dir[ 5 ];

class  CP{
public :
     int   operator ()( int  t1, int  t2){
         return  f[t1] > f[t2];
    }
};

int  astar(){
     int  i;

    f[ 0 ] =- 1 ;
    memset(mk, 0 , sizeof (mk)); // 0：未入队； 1：在open队中； 2：在closed队中
    priority_queue < int ,vector < int > ,CP  >  qu;

    g[st] = 0 ;
    f[st] = g[st] + hamilton(st / 10 );
    qu.push(st);
    mk[st] = 1 ;

     while ( ! qu.empty()){
        s = qu.top();
        qu.pop();

        op = s % 10 ;
        x = tile_x(s / 10 );
        y = tile_y(s / 10 );

         if (s / 10 == ed)
             return  g[s];
        mk[s] = 2 ;

        nop = (op + 1 ) % 4 ;
        ns = s / 10 * 10 + nop;
         if (mk[ns] == 0 ){
            g[ns] = g[s] + 1 ;
            f[ns] = f[s] + 1 ;
            qu.push(ns);
            mk[ns] = 1 ;
        }
         else   if (mk[ns] == 1 ){
             if (g[s] + 1 < g[ns]){
                g[ns] = g[s] + 1 ;
                qu.push( 0 ); // 更新堆
                qu.pop();
            }
        }


        nop = (op + 3 ) % 4 ;
        ns = s / 10 * 10 + nop;
         if (mk[ns] == 0 ){
            g[ns] = g[s] + 1 ;
            f[ns] = f[s] + 1 ;
            qu.push(ns);
            mk[ns] = 1 ;
        }
         else   if (mk[ns] == 1 ){
             if (g[s] + 1 < g[ns]){
                g[ns] = g[s] + 1 ;
                qu.push( 0 );
                qu.pop();
            }
        }

         for (i = 1 ;i <= 3 ;i ++ ){
             if (op == 0 )
                x -- ;
             if (op == 1 )
                y ++ ;
             if (op == 2 )
                x ++ ;
             if (op == 3 )
                y -- ;

             if (x <= 1   ||  x >= n  ||  y <= 1   ||  y >= m  ||  graph[x][y] == 1 )
                 break ;

            ns = tile(x,y);
            ns = ns * 10 + op;
             if (mk[ns] == 0 ){
                g[ns] = g[s] + 1 ;
                f[ns] = g[ns] + hamilton(ns / 10 );
                qu.push(ns);
                mk[ns] = 1 ;
            }
             else   if (mk[ns] == 1 ){
                 if (g[s] + 1 < g[ns]){
                    g[ns] = g[s] + 1 ;
                    qu.push( 0 );
                    qu.pop();
                }
            }
        }
    }
     return   - 1 ;
}


int  main(){
     int  i,j,tmp,x,y;
     while (scanf( " %d%d " , & n, & m)  &&  n  &&  m){
        memset(graph, 0 , sizeof (graph));
        n ++ ;m ++ ;
         for (i = 2 ;i <= n;i ++ ){
             for (j = 2 ;j <= m;j ++ ){
                scanf( " %d " , & tmp);
                 if (tmp)
                    graph[i][j] = graph[i - 1 ][j] = graph[i][j - 1 ] = graph[i - 1 ][j - 1 ] = 1 ;
            }
        }

         /*
        printf("\n");
        for(i=1;i<=n;i++){
            for(j=1;j<=m;j++)
                printf("%d ",graph[i][j]);
            printf("\n");
        }
        printf("\n"); */


        scanf( " %d%d " , & x, & y);
        x ++ ;y ++ ;
        st = tile(x,y);
        scanf( " %d%d " , & x, & y);
        x ++ ;y ++ ;
        ed = tile(x,y);

        scanf( " %s " ,dir);

         if (st == ed)
            printf( " 0\n " );
         else {
             if (dir[ 0 ] == ' n ' )
                st = st * 10 ;
             if (dir[ 0 ] == ' e ' )
                st = st * 10 + 1 ;
             if (dir[ 0 ] == ' s ' )
                st = st * 10 + 2 ;
             if (dir[ 0 ] == ' w ' )
                st = st * 10 + 3 ;
            printf( " %d\n " ,astar());

        }
    }
     return   0 ;
}