#include<bits/stdc++.h>
using namespace std;
#include "dreaming.h"
const int MAXN = 101010;
vector<pair<int, int>> conn[MAXN];
int dis1[MAXN];
int dis2[MAXN];
bool vis[MAXN];
vector<int> comp;
void dfs(int a, int pa, int d, int *dis, bool pcomp)
{
if(pcomp) comp.push_back(a);
dis[a] = d;
for(auto [x, w]: conn[a])
if(x != pa)
dfs(x, a, d+w, dis, pcomp);
}
int travelTime(int N, int M, int L, int A[], int B[], int T[]) {
for(int i=0; i<M; ++i)
{
conn[A[i]].emplace_back(B[i], T[i]);
conn[B[i]].emplace_back(A[i], T[i]);
}
int ans = 0;
vector<int> rads;
int tp = 1;
for(int i=0; i<N; ++i)
{
if(vis[i]) continue;
dfs(i, -1, 0, dis1, true);
int maxd = 0;
int maxi = i;
for(auto x: comp)
if(dis1[x]>maxd)
{
maxd = dis1[x];
maxi = x;
}
int d1 = maxi;
dfs(d1, -1, 0, dis2, false);
maxd = 0; maxi = d1;
for(auto x: comp)
{
if(dis2[x]>maxd)
{
maxd = dis2[x];
maxi = x;
}
}
int d2 = maxi;
dfs(d2, -1, 0, dis1, false);
int diam = dis1[d1];
int rad = diam;
for(auto x: comp)
rad = min(rad, max(dis1[x], dis2[x]));
ans = max(ans, diam);
rads.push_back(rad);
for(auto x: comp) vis[x] = true;
comp.clear();
}
sort(rads.rbegin(), rads.rend());
if(rads.size() >= 2)
ans = max(ans, rads[0] + rads[1] + L);
if(rads.size() >= 3)
ans = max(ans, rads[1] + rads[2] + 2*L);
return ans;
}
