HDU 5326 

 1 #include <cstdio>
 2 #include <iostream>
 3 #include <algorithm>
 4 #include <cstring>
 5 using namespace std;
 6 int vis[200];
 7 struct Point
 8 {
 9     int sum;
10     int last;
11 }s[200];
12 
13 int main()
14 {
15     int n,m;
16     while(~scanf("%d %d",&n,&m))
17     {
18         if(n==1&&m==0)//注意特判！！！
19         {
20             printf("1\n");
21             continue;
22         }
23         for(int i=0;i<=104;i++)
24             s[i].sum=0,s[i].last=0,vis[i]=0;
25         int x,y;
26         if(m>=n)
27         {
28             printf("0\n");
29             continue;
30         }
31         for(int i=0;i<n-1;i++)
32         {
33             scanf("%d %d",&x,&y);
34             s[y].last=x;
35             int ss=y;
36             if(!vis[y])
37             {
38                 while(1)
39                 {
40                   if(s[ss].last!=0)
41                     {
42                         s[s[ss].last].sum++;
43                        ss=s[ss].last;
44                     }
45                  else
46                     break;
47                 }
48             }
49             else
50             {
51                 int d=s[ss].sum+1;
52                 while(1)
53                   {
54                  if(s[ss].last!=0)
55                   {
56                      s[s[ss].last].sum+=d;
57                      ss=s[ss].last;
58                    }
59                  else
60                      break;
61                   }
62             }
63            ss=s[ss].last;
64             while(1)
65             {
66                 if(s[ss].last!=0)
67                 {
68                     s[s[ss].last].sum++;
69                     ss=s[ss].last;
70                 }
71                 else
72                     break;
73             }
74             vis[x]=vis[y]=1;
75         }
76   //      printf("%d\n",s[1].sum);
77         int ans=0;
78         for(int i=1;i<=100;i++)
79             if(m==s[i].sum&&vis[i])
80                 ans++;
81         printf("%d\n",ans);
82     }
83 }
84  

 

posted @ 2017-03-12 12:58  boom~  阅读(145)  评论(0)    收藏  举报