BFS-修改范例-开门系列-单扇多类门配多钥匙

/*
BFS:多类单个门，配多把钥匙
*/



#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <limits.h>
#include <malloc.h>
#include <ctype.h>
#include <math.h>
#include <string>
#include <iostream>
#include <algorithm>
using namespace std;
#include<queue>
const int INF = 999999;
struct node
{
    int x,y;        
};
struct DOOR
{
    int x,y;
    int find;
};
queue<node> q;
int n,m,time;
char mp[25][25];
int vis[25][25];
int key[5];
int skey[5];
DOOR door[5];
int xx[4]={1,-1,0,0};
int yy[4]={0,0,1,-1};

int bfs(int x,int y)
{
    while(!q.empty ())
        q.pop ();
    node from,next;
    int i;
    from.x=x,from.y=y;
    vis[x][y]=1;
    q.push (from);
    while(!q.empty ())
    {
        from=q.front ();
        q.pop ();
        for(i=0;i<4;i++)
        {
            int dx=from.x+xx[i];
            int dy=from.y+yy[i];
            if(dx>=0&&dx<n&&dy>=0&&dy<m&&vis[dx][dy]==0&&mp[dx][dy]!='X')
            {                
                next.x=dx;
                next.y=dy;
                if(mp[dx][dy]=='G') return 1;
                else if(mp[dx][dy]>='a'&&mp[dx][dy]<='e')//find the key                 
                {                    
                    vis[dx][dy]=1;
                    key[mp[dx][dy]-'a']++;
                    if(key[mp[dx][dy]-'a']==skey[mp[dx][dy]-'a']&&door[mp[dx][dy]-'a'].find==1)
                    {            
                        door[mp[dx][dy]-'a'].find=2;
                        node t;
                        t.x=door[mp[dx][dy]-'a'].x;
                        t.y=door[mp[dx][dy]-'a'].y;
                        vis[t.x][t.y]=1;
                        q.push (t);
                    }
                    q.push (next);
                }
                else if(mp[dx][dy]>='A'&&mp[dx][dy]<='E')//find the door
                {
                    door[mp[dx][dy]-'A'].x=dx;
                    door[mp[dx][dy]-'A'].y=dy;                    
                    door[mp[dx][dy]-'A'].find=1;
                    if(key[mp[dx][dy]-'A']==skey[mp[dx][dy]-'A']&&door[mp[dx][dy]-'A'].find==1)
                    {            
                        door[mp[dx][dy]-'A'].find=2;
                        node t;
                        t.x=door[mp[dx][dy]-'A'].x;
                        t.y=door[mp[dx][dy]-'A'].y;
                        vis[t.x][t.y]=1;
                        q.push (t);
                    }
                }
                else 
                {
                    vis[dx][dy]=1;
                    q.push (next);
                }
            }
        }
    }        
    return 0;
}

int main()
{
    int i,j;
    int x,y;
    while(scanf("%d%d",&n,&m)!=EOF)
    {
        if(n==0&&m==0) break;
        memset(mp,0,sizeof(mp));
        memset(vis,0,sizeof(vis));
        memset(key,0,sizeof(key));
        memset(skey,0,sizeof(skey));
        memset(door,0,sizeof(door));        
        for(i=0;i<n;i++)
        {            
            scanf("%s",mp[i]);
            for(j=0;j<m;j++)   
            {
                if(mp[i][j]=='S')
                    x=i,y=j;                                            
                if(mp[i][j]>='a'&&mp[i][j]<='e')
                    skey[mp[i][j]-'a']++;
            }
        }        
        int ans=bfs(x,y);
        if(ans==1)
            printf("YES\n");            
        else
            printf("NO\n");
        
    }
    return 0;
}



/*
4 4
Saaa
aaaa
XXAX
GBbb



*/