#include<bits/stdc++.h>
using namespace std;const int N=1e5+7,M=5e6+7,p=1e9+7;typedef long long ll;
int ans,f[N],inv[N],f_[N],rtt,trt,n,m,cnt,k,w[N],w2[N],sz[N],rt[N],lc[M],rc[M],v[M];
ll d[N];vector<int>G[N],G2[N];set<ll>s[N];
int sunion(int u,int v){
	if(s[u].size()<s[v].size())swap(u,v);
	for(auto it:s[v])s[u].insert(it);return u;
}
void dfs(int u,int v){
	s[rt[u]=u].insert(d[u]);for(int i=0;i<G[u].size();++i)if(G[u][i]!=v)
	d[G[u][i]]=d[u]+G2[u][i],dfs(G[u][i],u),rt[u]=sunion(rt[u],rt[G[u][i]]);
	while(!s[rt[u]].empty()){
		auto it=s[rt[u]].end();it--;if(*it<=d[v]+k)break;
		w[u]++;s[rt[u]].erase(it);
	}
}
void dfs2(int u,int v,int n){
	int t=0;sz[u]=1;for(auto i:G[u])if(i&&i!=v)dfs2(i,u,n),sz[u]+=sz[i],t=max(t,sz[i]);
	t=max(t,n-sz[u]);if(t<trt)trt=t,rtt=u;
}
void upd(int &o,int l,int r,int x){
	if(!o)o=++cnt,lc[o]=rc[o]=v[o]=0;v[o]++;
	if(l==r)return;int mid=(l+r)/2;
	if(x<=mid)upd(lc[o],l,mid,x);else upd(rc[o],mid+1,r,x);
}
void qry(int o,int l,int r,int x,int &w){
	if(!o||x<l)return;if(r<=x){w+=v[o];return;}
	int mid=(l+r)/2;qry(lc[o],l,mid,x,w);qry(rc[o],mid+1,r,x,w);
}
void dfs3(int u,int v,int x){
	if(x>k)return;qry(rtt,0,k,k-x,w2[u]);
	for(int i=0;i<G[u].size();++i)if(G[u][i]&&G[u][i]!=v)dfs3(G[u][i],u,x+G2[u][i]);
}
void dfs4(int u,int v,int x){
	if(x>k)return;upd(rtt,0,k,x);
	for(int i=0;i<G[u].size();++i)if(G[u][i]&&G[u][i]!=v)dfs4(G[u][i],u,x+G2[u][i]);
}
void divide(int u,int n){
	trt=1e9;dfs2(u,0,n);dfs2(u=rtt,0,n);cnt=rtt=0;upd(rtt,0,k,0);
	for(int i=0;i<G[u].size();++i)if(G[u][i]){
		dfs3(G[u][i],u,G2[u][i]),dfs4(G[u][i],u,G2[u][i]);
	}
	cnt=rtt=0;for(int i=G[u].size()-1;~i;--i)if(G[u][i]){
		dfs3(G[u][i],u,G2[u][i]),dfs4(G[u][i],u,G2[u][i]);
	}
	qry(rtt,0,k,k,w2[u]);w2[u]++;
	for(auto i:G[u])if(i){
		for(int j=0;j<G[i].size();++j)if(G[i][j]==u){G[i][j]=0;break;}
		divide(i,sz[i]);
	}
}
int calc(int x){return x<m?0:1ll*f[x]*f_[x-m]%p;}
int main(){
	scanf("%d%d%d",&n,&m,&k);
	f[0]=f_[0]=1;for(int i=1;i<=n;++i){
		f[i]=1ll*f[i-1]*i%p;inv[i]=(i==1?1:1ll*(p-p/i)*inv[p%i]%p);
		f_[i]=1ll*f_[i-1]*inv[i]%p;
	}
	for(int i=1,u,v,w;i<n;++i){
		scanf("%d%d%d",&u,&v,&w);
		G[u].push_back(v);G[v].push_back(u);
		G2[u].push_back(w);G2[v].push_back(w);
	}
	dfs(1,0);divide(1,n);w[1]=w2[1];
	for(int i=1;i<=n;++i)ans=(1ll*ans+calc(w2[i])+p-calc(w2[i]-w[i]))%p;
	printf("%d\n",ans);
}