#include <cstdio>

 #include <cstring>

 #include <iostream>

 #include <vector>

 #include <algorithm>

 using namespace std;

 #define N 10005

 int n , m , k , first[N];

 struct Edge{

     int y , next , d;

     Edge(){}

     Edge(int y , int next , int d):y(y),next(next),d(d){}

 }e[N<<];

 void add_edge(int x , int y , int d)

 {

     e[k] = Edge(y , first[x] , d);

     first[x] = k++;

 }

 int sz[N] , dis[N] , f[N] , d[N] , cnt , root , ret;

 bool use[N];

 void find_root(int u , int fa , int size)

 {

     sz[u] =  , f[u] = ;

     int v;

     for(int i=first[u] ; ~i ; i=e[i].next){

         if(use[v=e[i].y] || v==fa) continue;

         find_root(v , u , size);

         sz[u] += sz[v] ;

         f[u] = max(f[u] , sz[v]);

     }

     f[u] = max(f[u] , size-sz[u]);

     if(f[u]<f[root]) root = u;

 }

 void dfs(int u , int fa)

 {

     d[cnt++] = dis[u];

     sz[u] = ;

     int v;

     for(int i=first[u] ; ~i ; i=e[i].next){

         if(use[v=e[i].y] || v==fa) continue;

         dis[v] = dis[u]+e[i].d;

         if(dis[v]>m) continue;

         dfs(v , u);

         sz[u] += sz[v];

     }

 }

 int cal(int u , int val)

 {

     dis[u] = val , cnt=;

     dfs(u , );

     sort(d , d+cnt);

     int ret = ;

     for(int l= , r=cnt- ; l<r ; )

         if(d[l]+d[r]<=m) ret+=r-l++;

         else r--;

     return ret;

 }

 void solve(int u)

 {

     ret+=cal(u , );

     use[u] =true;

     int v;

     for(int i=first[u] ; ~i ; i=e[i].next){

         if(use[v=e[i].y]) continue;

         ret -= cal(v , e[i].d);

         find_root(v , root= , sz[v]);

         solve(root);

     }

 }

 int main()

 {

    // freopen("in.txt" , "r" , stdin);

     int x,y,d;

     while(scanf("%d%d" , &n , &m) , n+m)

     {

         memset(first , - , sizeof(first));

         k = ;

         for(int i= ; i<n ; i++){

             scanf("%d%d%d" , &x , &y , &d);

             add_edge(x , y , d);

             add_edge(y , x , d);

         }

         memset(use ,  , sizeof(use));

         ret= , f[] = 1e9;

         find_root( , root= , n);

         solve(root);

         printf("%d\n" , ret);

     }

 }