#include <cstdio>

#include <cstring>

#include <iostream>

#include <algorithm>

#define maxn 20005

#define inf 0x3f3f3f3f

using namespace std;

int n,k,h[maxn],to[maxn],ne[maxn],w[maxn],en,cnt;

int a[maxn],b[maxn],ban[maxn],siz[maxn],size,root;

int mx[maxn],now,now_mx,tot;

void init(){en=cnt=0;memset(h,-1,sizeof h);memset(ban,0,sizeof ban);}

void add(int a,int b,int c){to[en]=b;w[en]=c;ne[en]=h[a];h[a]=en++;}

void rd(){for(int i=1;i<n;++i){int a,b,c;scanf("%d%d%d",&a,&b,&c);add(a,b,c);add(b,a,c);}}

void dfs_size(int o,int fa)

{

	siz[o]=1;

	mx[o]=0;

	for (int i=h[o];i>=0;i=ne[i])

	if (to[i]!=fa&&!ban[to[i]]){

		dfs_size(to[i],o);

		siz[o]+=siz[to[i]];

		mx[o]=max(mx[o],siz[to[i]]);

	}

}

void dfs_root(int o,int fa)

{

	int now=max(mx[o],size-siz[o]);

	if (now<now_mx) now_mx=now,root=o;

	for (int i=h[o];i>=0;i=ne[i]) if (to[i]!=fa&&!ban[to[i]]) dfs_root(to[i],o);

}

void dfs_dist(int o,int fa,int dist)

{

	a[++tot]=dist;

	for (int i=h[o];i>=0;i=ne[i])

		if (to[i]!=fa&&!ban[to[i]])

			dfs_dist(to[i],o,dist+w[i]);

}

int cal()

{

	int ret=0,j=tot;

	sort(a+1,a+tot+1);

	for (int i=1;i<=tot;++i)

	{

		while (a[j]+a[i]>k&&j) j--;

		ret+=j;

		if (j>i) ret--;

	}

	return ret/2;

}

void dfs(int o)

{

	dfs_size(o,0);

	size=siz[o];

	now_mx=inf;

	dfs_root(o,0);

	ban[root]=1;

	for (int i=h[root];i>=0;i=ne[i])

	{

		if (!ban[to[i]])

		{

			tot=0;

			dfs_dist(to[i],root,w[i]);

			cnt-=cal();

		}

	}

	tot=0;

	dfs_dist(root,0,0);

	cnt+=cal();

	for (int i=h[root];i>=0;i=ne[i])

		if (!ban[to[i]])

			dfs(to[i]);

}

int main()

{

	while (scanf("%d%d",&n,&k)!=EOF&&n&&k)

	{

		init();rd();dfs(1);

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

	}

}