#include "traffic.h"
// #pragma GCC target("avx2")
#pragma GCC optimize("O3", "unroll-loops")
// #include <bits/extc++.h>
// using namespace __gnu_pbds;
#include <bits/stdc++.h>
using namespace std;
// #define int long long
// template <typename T>
// using pbds_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
using pii = pair<int, int>;
template<typename T>
using prior = priority_queue<T, vector<T>, greater<T>>;
template<typename T>
using Prior = priority_queue<T>;
#define X first
#define Y second
#define fastIO() ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)
#define RANDOM() random_device __rd; \
mt19937 __gen = mt19937(__rd()); \
uniform_int_distribution<int> __dis(0, 1); \
auto rnd = bind(__dis, __gen);
const int INF = 2E9;
const int mod = 1E9 + 7;
const int maxn = 1E6 + 5;
int sum = 0, minAns = INF, ans = 0;
vector<int> adj[maxn], sz(maxn);
void dfs(int now, int lst) {
int maxChild = 0;
for (auto x : adj[now]) {
if (x == lst) continue;
dfs(x, now);
sz[now] += sz[x];
maxChild = max(maxChild, sz[x]);
}
if (max(maxChild, sum - sz[now]) < minAns) {
minAns = max(maxChild, sum - sz[now]);
ans = now;
}
}
int LocateCentre(int N, int P[], int S[], int D[]) {
for (int i = 0; i < N; ++i) sum += (sz[i] = P[i]);
for (int i = 0; i < N-1; ++i) {
adj[S[i]].push_back(D[i]);
adj[D[i]].push_back(S[i]);
}
dfs(0, -1);
return ans;
}
/*
int32_t main() {
fastIO();
return 0;
}*/
