#include<bits/stdc++.h>
using namespace std;
#define int long long
#define REP(i,m,n) for(int i=(m);i<(n);i++)
#define rep(i,n) REP(i,0,n)
#define pb push_back
#define all(a) a.begin(),a.end()
#define rall(c) (c).rbegin(),(c).rend()
#define mp make_pair
#define endl '\n'
#define vec vector<ll>
#define mat vector<vector<ll> >
#define fi first
#define se second
#define double long double
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll,ll> pll;
//typedef long double ld;
typedef complex<double> Complex;
const ll INF=1e9+7;
const ll MOD=INF;
const ll inf=INF*INF;
const ll mod=MOD;
const ll MAX=100010;

signed main(){
    ll n,m,k;cin>>n>>m>>k;
    vector<vector<pll> >G(n);
    rep(i,m){
        ll x,y,z;
        cin>>x>>y>>z;
        x--;y--;
        G[x].pb(mp(y,z));
        G[y].pb(mp(x,z));
    }
    ll ans=1;
    {
    queue<ll>q;
    vector<ll>mi(n,1),ma(n,k);
    vector<ll>used(n);
    rep(i,n){
        if(used[i])continue;
        q.push(i);
        used[i]=1;
        ll res=k;
        while(!q.empty()){
            ll v=q.front();
            q.pop();
            res=min(res,ma[v]-mi[v]+1);
            for(auto e:G[v]){
                if(!used[e.fi]){
                    q.push(e.fi);
                    used[e.fi]=1;
                }
                mi[e.fi]=max(mi[e.fi],e.se-ma[v]);
                ma[e.fi]=min(ma[e.fi],e.se-mi[v]);
                mi[e.fi]=min(mi[e.fi],k);
                ma[e.fi]=max(ma[e.fi],1LL);
            }
        }
        res=max(res,0LL);
        ans=ans*res%mod;
    }
    }
    ll ans2=1;
    k=k-1;
    {
    queue<ll>q;
    vector<ll>mi(n,1),ma(n,k);
    vector<ll>used(n);
    ll ans=1;
    rep(i,n){
        if(used[i])continue;
        q.push(i);
        used[i]=1;
        ll res=k;
        while(!q.empty()){
            ll v=q.front();
            q.pop();
            res=min(res,ma[v]-mi[v]+1);
            for(auto e:G[v]){
                if(!used[e.fi]){
                    q.push(e.fi);
                    used[e.fi]=1;
                }
                mi[e.fi]=max(mi[e.fi],e.se-ma[v]);
                ma[e.fi]=min(ma[e.fi],e.se-mi[v]);
                mi[e.fi]=min(mi[e.fi],k);
                ma[e.fi]=max(ma[e.fi],1LL);
            }
        }
        res=max(res,0LL);
        ans=ans*res%mod;
    }
        ans2=ans;
    }
    ll an=(ans-ans2+mod)%mod;
    cout<<an<<endl;
}