#include "dreaming.h"
#include <bits/stdc++.h>
using namespace std;
#define UP1(i, n) for (int i = 0; i < (n); i++)
#define UP2(i, a, b) for (int i = (a); i <= (b); i++)
#define UP3(i, a, b, c) for (int i = (a); i <= (b); i += (c))
#define DN1(i, n) for (int i = (n) - 1; i >= 0; i--)
#define DN2(i, a, b) for (int i = (a); i >= (b); i--)
#define DN3(i, a, b, c) for (int i = (a); i >= (b); i -= (c))
#define FOR_IMPL(_1, _2, _3, _4, NAME, ...) NAME
#define FOR_UP(...) FOR_IMPL(__VA_ARGS__, UP3, UP2, UP1) (__VA_ARGS__)
#define FOR_DN(...) FOR_IMPL(__VA_ARGS__, DN3, DN2, DN1) (__VA_ARGS__)
#define POPCOUNT(n) __builtin_popcountll(n)
#define CLZ(n) __builtin_clzll(n)
#define CTZ(n) __builtin_ctzll(n)
#define LOG(n) __lg(n)
#define BIT(n, i) (((n) >> (i)) & 1LL)
#define FLIP(n, i) ((n) ^ (1LL << (i)))
#define ON(n, i) ((n) | (1LL << (i)))
#define OFF(n, i) ((n) & ~(1LL << (i)))
#define all(x) (x).begin(), (x).end()
#define len(x) (int)x.size()
#define fi first
#define se second
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using pii = pair<int, int>;
using pll = pair<long long, long long>;
#if __cplusplus <= 201402L
template <typename T> T gcd(T a, T b) {
return __gcd(a, b);
}
template <typename T> T lcm(T a, T b) {
return a / gcd(a, b) * b;
}
#endif
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
long long rand(long long l, long long r) {
return uniform_int_distribution<long long>(l, r)(rng);
}
template <class T> void remove_duplicate(vector<T> &v) {
sort(v.begin(), v.end());
v.resize(unique(v.begin(), v.end()) - v.begin());
}
template <class T> bool maximize(T &x, const T &y) {
if (x < y) {
x = y;
return true;
}
return false;
}
template <class T> bool minimize(T &x, const T &y) {
if (x > y) {
x = y;
return true;
}
return false;
}
const int N = 1e5 + 24;
const ll INF = 1e18;
int n, m, L; vector<pii> g[N];
bool vis[N]; int cntComp;
ll f[N], minF[N];
void dfs(int u, int pre) {
vis[u] = 1;
for (auto [v, w]: g[u]) if (v != pre) {
dfs(v, u);
maximize(f[u], f[v] + w);
}
}
void calc(int u, int pre) {
// cout << u << ' ' << f[u] << endl;
minimize(minF[cntComp], f[u]);
multiset<ll> setF;
for (auto [v, w]: g[u]) {
setF.insert(f[v] + w);
}
for (auto [v, w]: g[u]) if (v != pre) {
ll save_u = f[u], save_v = f[v];
setF.erase(setF.find(f[v] + w));
f[u] = (len(setF) ? *setF.rbegin() : 0);
maximize(f[v], f[u] + w);
calc(v, u);
f[u] = save_u, f[v] = save_v;
setF.insert(f[v] + w);
}
}
int travelTime(int n_, int m_, int L_, int a[], int b[], int t[]) {
n = n_, m = m_, L = L_;
FOR_UP (i, m) {
int u = a[i] + 1, v = b[i] + 1;
int w = t[i];
g[u].push_back({v, w});
g[v].push_back({u, w});
}
FOR_UP (i, 1, n) {
if (!vis[i]) {
++cntComp;
minF[cntComp] = INF;
dfs(i, 0);
calc(i, 0);
}
}
multiset<ll> setF;
FOR_UP (i, 1, cntComp) {
// cout << minF[i] << '\n';
setF.insert(minF[i]);
}
ll res = 0;
while (len(setF) > 1) {
ll u = *setF.begin(); setF.erase(setF.find(u));
ll v = *setF.rbegin(); setF.erase(setF.find(v));
maximize(res, u + v + L);
setF.insert(max(u + L, v));
}
return res;
}
#ifdef LOCAL
int main() {
cin.tie(0) -> sync_with_stdio(0);
int n, m, l; cin >> n >> m >> l;
int A[m], B[m], T[m];
FOR_UP (i, m) {
cin >> A[i] >> B[i] >> T[i];
}
cout << travelTime(n, m, l, A, B, T);
}
#endif
