1 #include <cstdio>
 2 #include <cstring>
 3 #include <iostream>
 4 using namespace std;
 5 
 6 struct node
 7 {
 8     int next, to;   
 9     int step;
10 } a[100005];
11 
12 int head[100005];
13 int n, d, len, ans;
14 
15 void Add(int x, int y)
16 {
17     a[len].to = y;
18     a[len].next = head[x];
19     head[x] = len++;
20 }
21 
22 void Dfs(int x, int step)
23 {
24     int i, j, k;
25     if(head[x] == -1)
26         return;
27     for(i = head[x]; i!=-1; i = a[i].next)  
28     {  
29         k = a[i].to;  
30         a[i].step = step+1;  //这里的step和结构体里边的不一样； 
31        if(a[i].step>d)      
32            ans++;  
33        Dfs(k,a[i].step);    //结构体已经清零。 
34    }  
35 
36 }
37 
38 int main()
39 {
40     int t, i, j, x, y;
41     while(~scanf("%d", &t))
42     {
43         while(t--)
44         {
45             memset(head, -1, sizeof(head));
46             memset(a, 0, sizeof(a));
47             scanf("%d %d", &n, &d);
48             len = 0;
49             for(i=1; i<n; i++)
50             {
51                 scanf("%d %d", &x, &y);
52                 Add(x, y);
53             }
54             ans = 0;
55             Dfs(0, 0);
56             printf("%d\n", ans);
57         } 
58     }
59     return 0;
60 }

 1 #include <vector>
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <iostream>
 5 #include <algorithm>
 6 using namespace std;
 7 int dis[100005];  vector<int>v[100005];
 8 void Dfs(int x)
 9 {
10     for(int i = 0; i < v[x].size(); i++)
11     {
12         dis[v[x][i]] = dis[x] + 1;
13         Dfs(v[x][i]);
14     }
15     return;
16 }
17 int main()
18 {
19     int t;
20     scanf("%d", &t);
21     while(t--)
22     {
23         int n, m, x, y;
24         scanf("%d %d", &n, &m);
25         for(int i=1; i < n; i++)
26             v[i].clear();
27         for(int i=1; i<n; i++)
28         {
29             scanf("%d %d", &x, &y); 
30             v[x].push_back(y);
31         }
32         memset(dis, 0, sizeof(dis));  //数组清0， 保存路径经过结点个数；  
33         Dfs(0);
34         int ans = 0;
35         for(int i=1; i<n; i++)   
36         {
37             if(dis[i] > m)
38             ans++;
39         }
40         printf("%d\n", ans);
41     }
42     return 0;
43 }