HDU 1026 Ignatius and the Princess I （BFS）

题目链接

题意 ： 从（0,0）点走到（N-1，M-1）点，问最少时间。

思路 ： BFS、、、、、

 1 #include <stdio.h>
 2 #include <string.h>
 3 #include <queue>
 4 #include <iostream>
 5
 6 using namespace std ;
 7
 8 struct node
 9 {
10     int x,y ;
11     int tim ;
12     friend bool operator < (node a,node b)
13     {
14         return a.tim > b.tim ;
15     }
16 } temp,temp1;
17 int N,M ,t;
18 char mapp[110][110] ;
19 int vis[110][110] ;
20 int dir[4][2] = {{-1,0},{1,0},{0,-1},{0,1}} ;
21
22 int BFS()
23 {
24     temp.x = 0 ;
25     temp.y = 0 ;
26     temp.tim = 0 ;
27     priority_queue<node>Q ;
28     Q.push(temp) ;
29    // vis[0][0] = true ;
30     while(Q.size())
31     {
32         temp = Q.top() ;
33         Q.pop() ;
34         if(temp.x == N-1 && temp.y == M-1) return temp.tim ;
35         for(int i = 0 ; i < 4 ; i++)
36         {
37             temp1.x = temp.x+dir[i][0] ;
38             temp1.y = temp.y+dir[i][1] ;
39             if(temp1.x >= 0 && temp1.y >= 0 && temp1.x <= N-1 && temp1.y <= M-1 && vis[temp1.x][temp1.y] == -1 && mapp[temp1.x][temp1.y] != ‘X‘)
40             {
41                 vis[temp1.x][temp1.y] = temp.x*M+temp.y ;
42                 if(mapp[temp1.x][temp1.y] == ‘.‘)
43                     temp1.tim = temp.tim+1 ;
44                 else
45                     temp1.tim = temp.tim + mapp[temp1.x][temp1.y]-‘0‘+1 ;
46                 Q.push(temp1) ;
47             }
48         }
49     }
50     return -1 ;
51 }
52 void print(int x,int y)
53 {
54     if(x == 0 && y == 0)
55         return ;
56     int xx = vis[x][y]/M ;
57     int yy = vis[x][y]%M ;
58     print(xx,yy) ;
59     printf("%ds:(%d,%d)->(%d,%d)\n",t++,xx,yy,x,y) ;
60     if(mapp[x][y] >= ‘0‘ && mapp[x][y] <= ‘9‘)
61     {
62         while(mapp[x][y] -‘0‘ > 0)
63         {
64             printf("%ds:FIGHT AT (%d,%d)\n",t++,x,y) ;
65             mapp[x][y] -- ;
66         }
67     }
68 }
69 int main()
70 {
71     while(~scanf("%d %d",&N,&M))
72     {
73         for(int i = 0 ; i < N ; i++ )
74             scanf("%s",mapp[i]) ;
75         memset(vis,-1,sizeof(vis)) ;
76         int timee = BFS() ;
77         if(timee == -1)
78         {
79             printf("God please help our poor hero.\nFINISH\n") ;
80         }
81         else
82         {
83             t = 1 ;
84             printf("It takes %d seconds to reach the target position, let me show you the way.\n",timee) ;
85             print(N-1,M-1) ;
86             printf("FINISH\n") ;
87         }
88     }
89     return 0 ;
90 }