#include <bits/stdc++.h>
using namespace std;
#define sp << ' ' <<
#define nl << '\n'
#include "dreaming.h"
const int MAXN = 1e5, INF = 2e9;
vector<array<int, 2>> g[MAXN];
int a[MAXN], b, x, y, ans = -1;
bitset<MAXN> vis;
void dfs(int u, int d, int p = -1){
vis[u] = 1;
a[u] = max(a[u], d);
if(d > x) x = d, y = u;
if(d < 0) b = min(b, a[u]);
for(auto &e : g[u]) if(e[0] != p) dfs(e[0], d < 0 ? d : d + e[1], u);
}
int travelTime(int n, int m, int L, int A[], int B[], int T[]){
for(int i=0; i<m; ++i){
g[A[i]].push_back({B[i], T[i]});
g[B[i]].push_back({A[i], T[i]});
}
priority_queue<int> q;
for(int i=0; i<n; ++i){
if(vis[i]) continue;
x = y = -1, b = INF;
dfs(i, 0), dfs(y, 0), dfs(y, 0);
ans = max(ans, x);
dfs(i, -1);
q.push(-b);
while(q.size() > 3) q.pop();
}
int a3 = -q.top(); q.pop();
if(q.empty()) return ans;
int a2 = -q.top(); q.pop();
if(q.empty()) return max(ans, a2 + a3 + L);
int a1 = -q.top(); q.pop();
return max(ans, max(a1 + a2 + L, a2 + a3 + L + L));
}
