#include "dreaming.h"
#include<bits/stdc++.h>
#define ll long long
#define pb push_back
#define mp make_pair
#define fi first
#define se second
using namespace std;
ll i,b[1010101],ma1,ma2,i1,hz,a[1010101],ma;
vector<pair<ll,ll> > v[1010101];
vector<ll> v1;
ll rmt(ll aa,ll bb)
{
if(bb>ma1)
{
ma1=bb;
i1=aa;
}
b[aa]=1;
ll ii;
for(ii=0;ii<v[aa].size();ii++)
{
if(b[v[aa][ii].fi]==0)
{
rmt(v[aa][ii].fi,bb+v[aa][ii].se);
}
}
}
ll rct(ll aa,ll bb)
{
ma2=max(ma2,bb);
b[aa]=2;
ll ii;
for(ii=0;ii<v[aa].size();ii++)
{
if(b[v[aa][ii].fi]==1)
{
rct(v[aa][ii].fi,bb+v[aa][ii].se);
}
}
}
ll rrt(ll aa,ll bb,ll cc)
{
a[cc]=bb;
if(bb==ma2)
{
ll ii;
for(ii=1;ii<=cc;ii++)
{
hz=min(hz,max(ma2-a[ii],a[ii]));
}
}
b[aa]=3;
ll ii;
for(ii=0;ii<v[aa].size();ii++)
{
if(b[v[aa][ii].fi]==2)
{
rrt(v[aa][ii].fi,bb+v[aa][ii].se,cc+1);
}
}
}
int travelTime(int N, int M, int L, int A[], int B[], int T[]) {
for(i=0;i<M;i++)
{
v[A[i]].pb(mp(B[i],T[i]));
v[B[i]].pb(mp(A[i],T[i]));
}
for(i=0;i<N;i++)
{
if(b[i]==0)
{
ma1=0;
ma2=0;
hz=10e17;
rmt(i,0);
rct(i1,0);
rrt(i1,0,1);
v1.pb(hz);
ma=max(ma,ma2);
// cout<<hz<<"\n";
}
}
sort(v1.begin(),v1.end());
reverse(v1.begin(),v1.end());
if(v1.size()==1)
return ma;
else
if(v1.size()==2)
return max(ma,v1[0]+v1[1]+L);
else
return max(ma,max(v1[0]+v1[1]+L,v1[1]+v1[2]+L+L));
return 42;
}
