#include<bits/stdc++.h>
//#define name "InvMOD"
#ifndef name
#include "dreaming.h"
#endif // name
using namespace std;
#define sz(v) (int)(v).size()
#define all(v) (v).begin(), (v).end()
#define dbg(x) "[" << #x " = " << (x) << "]"
template<typename T> bool ckmx(T& a, const T& b){
if(a < b)
return a = b, true;
return false;
}
int travelTime(int n, int m, int L, int A[], int B[], int T[]){
vector<vector<int>> adj(n, vector<int>());
for(int i = 0; i < m; i++){
adj[A[i]].push_back(i);
adj[B[i]].push_back(i);
}
vector<int> d(n, -1);
function<void(int,int)> preDFS = [&](int x, int p) -> void{
d[x] = 0;
for(int id : adj[x]){
int v = A[id] ^ B[id] ^ x, w = T[id];
if(v != p){
preDFS(v, x);
ckmx(d[x], d[v] + w);
}
}
return;
};
function<int(int,int,int)> dp = [&](int x, int p, int dpar) -> int{
vector<int> mxDist = {dpar};
for(int id : adj[x]){
int v = A[id] ^ B[id] ^ x;
if(v != p) mxDist.push_back(d[v] + T[id]);
}
sort(all(mxDist), greater<int>());
int answer = mxDist[0];
for(int id : adj[x]){
int v = A[id] ^ B[id] ^ x;
if(v == p) continue;
int nDist = (mxDist[0] == d[v] + T[id] ? mxDist[1] : mxDist[0]);
answer = min(answer, dp(v, x, nDist + T[id]));
}
return answer;
};
vector<int> dist;
for(int i = 0; i < n; i++){
if(d[i] == -1){
preDFS(i, -1);
dist.push_back(dp(i, -1, 0));
}
}
sort(all(dist), greater<int>());
int answer = 0;
if(sz(dist) == 1){
answer = dist[0];
}
else if(sz(dist) == 2){
answer = dist[0] + L + dist[1];
}
else answer = max(dist[0] + L + dist[1], dist[1] + 2 * L + dist[2]);
return answer;
}
#ifdef name
int32_t main(){
freopen(name".INP", "r", stdin);
freopen(name".OUT", "w", stdout);
int n,m,L; cin >> n >> m >> L;
int A[m], B[m], T[m];
for(int i = 0; i < m; i++){
cin >> A[i] >> B[i] >> T[i];
}
cout << travelTime(n, m, L, A, B, T) << "\n";
return 0;
}
#endif // name
