#include "dreaming.h"
#include <bits/stdc++.h>
using namespace std;
vector<vector<pair<int, int>>> g;
vector<bool> vis;
int ans;
void calcd(int u, int p, int d_, vector<pair<int, int>> &a) {
vis[u] = 1;
a.push_back({u, d_});
for (auto [v, w] : g[u])
if (v ^ p)
calcd(v, u, d_ + w, a);
}
void getmax(int x) {
vector<pair<int, int>> d, d2;
calcd(x, x, 0, d);
int mx = -1, mxn;
for (auto [a, b] : d)
if (b > mx) mx = b, mxn = a;
d.clear();
calcd(mxn, mxn, 0, d);
int mx2 = -1, mxn2;
map<int, int> dd;
for (auto [a, b] : d) {
dd[a] = b;
if (b > mx2) mx2 = b, mxn2 = a;
}
calcd(mxn2, mxn2, 0, d2);
for (auto [a, b] : d2)
ans = min(ans, max(b, dd[a]));
}
int travelTime(int n, int m, int l, int a[], int b[], int t[]) {
g.resize(n), vis.resize(n);
for (int i = 0; i < m; i++) {
int u = a[i], v = b[i], w = t[i];
g[u].push_back({v, w});
g[v].push_back({u, w});
}
vector<int> mx;
for (int i = 0; i < n; i++)
if (!vis[i]) {
ans = 2e9;
getmax(i);
mx.push_back(ans);
}
sort(mx.rbegin(), mx.rend());
return mx.size() == 1 ? mx[0] : mx.size() == 2 ? mx[0] + mx[1] + l : max(mx[0] + mx[1] + l, mx[1] + mx[2] + 2 * l);
}
