#include <bits/stdc++.h>
#include "dreaming.h"
using namespace std;
using ll = long long;
using pii = pair<int, int>;
vector<int> h;
int n;
vector<vector<pii>> adj;
void dfs(int u, int p=-1, int w=0) {
h[u] = w;
for (auto [v, pe] : adj[u]) {
if (v==p) continue;
dfs(v, u, w+pe);
}
}
int diameter() {
h.assign(n, 0);
dfs(0);
int l=0;
for (int i=0; i<n; i++) {
if (h[l] < h[i]) {
l = i;
}
}
h.assign(n, 0);
dfs(l);
int mx=0;
for (int i=0; i<n; i++) {
mx = max(mx, h[i]);
}
return mx;
}
int travelTime(int N, int m, int l, int A[], int B[], int T[]) {
n = N;
adj.assign(n, {});
vector<vector<int>> grid(n, vector<int>(n, 0));
for (int i=0; i<m; i++) {
int u = A[i];
int v = B[i];
adj[A[i]].push_back({B[i], T[i]});
adj[B[i]].push_back({A[i], T[i]});
grid[u][v] = grid[v][u] = 1;
}
for (int i=0; i<n; i++) {
grid[i][i] = 1;
}
int ans = 1e9;
for (int i=0; i<n; i++) {
for (int j=0; j<n; j++) {
if (grid[i][j] == 0) {
adj[i].push_back({j, l});
adj[j].push_back({i, l});
ans = min(ans, diameter());
adj[i].pop_back();
adj[j].pop_back();
}
}
}
return ans;
}
