#include <dreaming.h>
#include <bits/stdc++.h>
using namespace std;
typedef long long lo;
typedef pair< lo,lo > PII;
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define fio() ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)
#define FOR for(int i=0;i<N;i++)
#define mid ((start+end)/2)
#define ort ((bas+son)/2)
const lo MAX = -1000000000000000000;
const lo MIN = 1000000000000000000;
const lo inf = 3000000000;
const lo KOK = 100000;
const lo LOG = 30;
const lo li = 100005;
const lo mod = 1000000007;
lo n,m,b[li],a[li],k,flag,t[li],l,mx,mx1,maxi[li],say,mn[li],ind,maxx,maxxx,maxx1,maxx2;
lo cev;
string s;
lo ok[li];
vector<PII> v[li];
inline void dfs(lo node,lo ata,lo der,lo basla){
//~ cout<<node<<" : : "<<ata<<endl;
for(lo i=0;i<(lo)v[node].size();i++){
int go=v[node][i].fi;
int co=v[node][i].se;
if(go==ata)continue;
dfs(go,node,der+co,basla);
}
if(!ok[node])ok[node]=say;
if(der>mx)ind=node;
mx=max(mx,der);
maxxx=max(maxxx,mx);
maxi[node]=max(maxi[node],der);
}
int travelTime(int N, int M, int L, int A[], int B[], int T[]) {
for(lo i=0;i<M;i++){
v[A[i]].pb(mp(B[i],T[i]));
v[B[i]].pb(mp(A[i],T[i]));
}
FOR mn[i]=inf;
say=1;
dfs(0,-1,0,0);
mx=0;
dfs(ind,-1,0,ind);
mx1=mx;
mx=0;
dfs(ind,-1,0,ind);
mx=0;
for(lo i=0;i<N;i++){
if(!ok[i]){say++;mx=0;dfs(i,-1,0,i);mx=0;dfs(ind,-1,0,ind);mx=0;dfs(ind,-1,0,ind);}
}
FOR{
//~ cout<<ok[i]<<endl;
mn[ok[i]]=min(mn[ok[i]],maxi[i]);
}
cev=0;
//~ cout<<say<<"**\n";
//~ say=2;
for(lo i=1;i<=say;i++){
cev+=mn[i];
maxx2=max(maxx2,mn[i]);
if(maxx2>maxx1)swap(maxx2,maxx1);
if(maxx1>maxx)swap(maxx,maxx1);
//~ cout<<mn[i]<<endl;
}
if(say==1){maxx1=-inf;maxx2=-inf;}
if(say==2){maxx2=-inf;}
cev=maxx+maxx1;
//~ cout<<mx<<" : ; "<<mx1<<endl;
return max(maxxx,max(cev+(L),maxx2+maxx1+2*L));
}
