优先队列 模板

 1 /*

 2 优先队列

 3 */

 4 

 5 #include<stdio.h>

 6 #include<iostream>

 7 #include<cstdlib>

 8 #include<string.h>

 9 #include<queue>

10 #define HH 11111111

11 using namespace std;

12 char a[202][202];

13 int visit[202][202];

14 int n,m;

15 int map[4][2]={{1,0},{0,1},{-1,0},{0,-1}};

16 struct node

17 {

18     friend bool operator< (node n1,node n2)

19     {

20         return n1.p>n2.p;

21     }

22     int p;

23     int x;

24     int y;

25 };

26 void bfs(int x,int y)

27 {

28     int i,x1,y1;

29     priority_queue<node>b;

30     while(!b.empty())

31     {

32         b.pop();

33     }

34     node tmp,tmp1;

35     tmp.x=x;

36     tmp.y=y;

37     tmp.p=0;

38     b.push(tmp);

39     visit[x][y]=1;

40     while(b.size()>0)

41     {

42         tmp=b.top();

43         b.pop();

44         for(i=0;i<4;i++)

45         {

46             x1=tmp.x+map[i][0];

47             y1=tmp.y+map[i][1];

48             if(x1>=1&&x1<=n && y1>=1&&y1<=m && visit[x1][y1]==0 && a[x1][y1]!='#')

49             {

50                 if(a[x1][y1]=='x')

51                     visit[x1][y1]=tmp.p+2;

52                 else if(a[x1][y1]=='.' || a[x1][y1]=='r')

53                     visit[x1][y1]=tmp.p+1;

54                 tmp1=tmp;

55                 tmp.x=x1;

56                 tmp.y=y1;

57                 tmp.p=visit[x1][y1];

58                 b.push(tmp);

59                 tmp=tmp1;

60                 if(a[x1][y1]=='r')return;

61             }

62         }

63     }

64 }

65 int main()

66 {

67     int i,j,num;

68     while(scanf("%d%d",&n,&m)>0)

69     {

70         for(i=1;i<=n;i++)

71             scanf("%s",a[i]+1);

72         memset(visit,0,sizeof(visit));

73         for(i=1;i<=n;i++)

74             for(j=1;j<=m;j++)

75             {

76                 if(a[i][j]=='a')

77                 {

78                     bfs(i,j);

79                 }

80             }

81         num=HH;

82         for(i=1;i<=n;i++)

83             for(j=1;j<=m;j++)

84             {

85                 if(a[i][j]=='r' && visit[i][j]!=0 && visit[i][j]<num)

86                     num=visit[i][j];

87             }

88         if(num==HH)

89             printf("Poor ANGEL has to stay in the prison all his life.\n");

90         else

91             printf("%d\n",num);

92     }

93     return 0;

94 }