#include <bits/stdc++.h>
#include "dreaming.h"
using namespace std;
vector <vector <pair <int, int>>> adj;
vector <bool> visited;
vector <int> f_out, f_in;
vector <vector <int>> prefix, suffix;
void dfs_out(int u, int father) {
visited[u] = true;
for (int i = 0; i < (int) adj[u].size(); i++) {
pair <int, int> neighbor = adj[u][i];
if (neighbor.first != father) {
dfs_out(neighbor.first, u);
f_out[u] = max(f_out[u], f_out[neighbor.first] + neighbor.second);
}
}
prefix[u].clear();
prefix[u].resize((int) adj[u].size() + 2);
prefix[u][0] = 0;
for (int i = 1; i <= (int) adj[u].size(); i++) {
prefix[u][i] = max(prefix[u][i - 1], f_out[adj[u][i - 1].first] + adj[u][i - 1].second);
}
suffix[u].clear();
suffix[u].resize((int) adj[u].size() + 2);
suffix[u][(int) adj[u].size() + 1] = 0;
for (int i = (int) adj[u].size(); i >= 1; i--) {
suffix[u][i] = max(suffix[u][i + 1], f_out[adj[u][i - 1].first] + adj[u][i - 1].second);
}
}
void dfs_in(int u, int father) {
for (int i = 0; i < (int) adj[u].size(); i++) {
pair <int, int> neighbor = adj[u][i];
if (neighbor.first == father) {
continue;
}
f_in[neighbor.first] = max(f_in[neighbor.first], f_in[u] + neighbor.second);
f_in[neighbor.first] = max(f_in[neighbor.first], max(prefix[u][i], suffix[u][i + 2]) + neighbor.second);
dfs_in(neighbor.first, u);
}
}
int solve(int u) {
int n = (int) adj.size();
visited.clear();
visited.resize(n, false);
dfs_out(u, -1);
dfs_in(u, -1);
int ans = 1000000007;
for (int i = 0; i < n; i++) {
if (visited[i] == true) {
ans = min(ans, max(f_in[u], f_out[u]));
}
}
return ans;
}
int travelTime(int n, int m, int l, int a[], int b[], int t[]) {
adj.resize(n);
visited.resize(n, false);
for (int i = 0; i < m; i++) {
adj[a[i]].push_back(make_pair(b[i], t[i]));
adj[b[i]].push_back(make_pair(a[i], t[i]));
}
int ans = 0;
f_out.resize(n, 0);
f_in.resize(n, 0);
prefix.resize(n);
suffix.resize(n);
for (int i = 0; i < n; i++) {
if (visited[i] == false) {
ans += solve(i);
}
}
/*for (int u = 0; u < n; u++) {
cout << max(f_out[u], f_in[u]) << " ";
} */
ans += l;
return ans;
}
