#include "dreaming.h"
#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
template<typename T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<typename T, typename U> using ordered_map = tree<T, U, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<ll> vll;
#define FOR(i,j,k,in) for(int i=(j); i < (k);i+=in)
#define FORD(i,j,k,in) for(int i=(j); i >=(k);i-=in)
#define REP(i,b) FOR(i,0,b,1)
#define REPD(i,b) FORD(i,b,0,1)
#define pb push_back
#define mp make_pair
#define ff first
#define ss second
#define all(x) begin(x), end(x)
#define MANY_TESTS int tcase; cin >> tcase; while(tcase--)
const double EPS = 1e-9;
const int MOD = 1e9+7;
const ll INFF = 1e18;
const int INF = 1e9;
const ld PI = acos((ld)-1);
const vi dy = {1, 0, -1, 0, -1, 1, 1, -1};
const vi dx = {0, 1, 0, -1, -1, 1, -1, 1};
void DBG(){cout << "]" << endl;}
template<typename T, typename ...U> void DBG(const T& head, const U... args){ cout << head << "; "; DBG(args...); }
#define dbg(...) cout << "Line(" << __LINE__ << ") -> [" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__);
#define chk() cout << "Check at line(" << __LINE__ << ") hit." << endl;
template<class T, unsigned int U>
ostream& operator<<(ostream& out, const array<T, U> &v){out << "["; REP(i, U) out << v[i] << ", "; out << "]"; return out;}
template <class T, class U>
ostream& operator<<(ostream& out, const pair<T, U> &par) {out << "[" << par.first << ";" << par.second << "]"; return out;}
template <class T>
ostream& operator<<(ostream& out, const set<T> &cont) { out << "{"; for( const auto &x:cont) out << x << ", "; out << "}"; return out; }
template <class T, class U>
ostream& operator<<(ostream& out, const map<T, U> &cont) {out << "{"; for( const auto &x:cont) out << x << ", "; out << "}"; return out; }
template<class T>
ostream& operator<<(ostream& out, const vector<T> &v){ out << "["; REP(i, v.size()) out << v[i] << ", "; out << "]"; return out;}
template<class T>
istream& operator>>(istream& in, vector<T> &v){ for(auto &x : v) in >> x; return in; }
int travelTime(int n, int m, int l, int A[], int B[], int T[]) {
vector<int> dist(n, -1);
vector<int> dist2(n, -1);
vector<bool> visited(n, false);
auto get_partition = [&](vector<vector<array<int, 2>>> &g, int s){
vector<int> curr_visited;
function<void(int, int, vector<int>&)> dfs = [&](int v, int p, vector<int> &dist){
curr_visited.pb(v);
if(p == -1) dist[v] = 0;
for(auto x : g[v]){
if(x[0] == p) continue;
dist[x[0]] = dist[v] + x[1];
dfs(x[0], v, dist);
}
};
dfs(s, -1, dist);
curr_visited.clear();
int fd = max_element(all(dist)) - dist.begin();
dfs(fd, -1, dist2);
curr_visited.clear();
int sd = max_element(all(dist2)) - dist2.begin();
dfs(sd, -1, dist);
array<int, 3> res = {INF, INF, -1};
for(int v : curr_visited){
if(dist[v] + dist2[v] < res[0] + res[1]){ // guarantees having vertex at the diameter, then we pick middle based on difference between 2
res = {dist[v], dist2[v], v};
}
else if(dist[v] + dist2[v] == res[0] + res[1] && abs(dist[v] - dist2[v]) < abs(res[0] - res[1])){
res = {dist[v], dist2[v], v};
}
}
// mark component
for(int v : curr_visited){
visited[v] = true;
dist[v] = dist2[v] = -1;
}
if(res[0] < res[1])
swap(res[0], res[1]);
return res;
};
vector<vector<array<int, 2>>> g(n);
REP(i, m){
g[A[i]].pb({B[i], T[i]});
g[B[i]].pb({A[i], T[i]});
}
vector<array<int, 3>> partitions;
REP(i, n){
if(!visited[i]){
partitions.pb(get_partition(g, i));
}
}
sort(all(partitions), greater<array<int, 3>>());
int first_ver = partitions[0][2];
FOR(i, 1, partitions.size(), 1){
int second_ver = partitions[i][2];
g[first_ver].pb({second_ver, l});
g[second_ver].pb({first_ver, l});
}
fill(all(visited), false);
auto ans = get_partition(g, 0);
return ans[0] + ans[1];
}
