#include <bits/stdc++.h>
#include "traffic.h"
using namespace std;
int peeps = 0;
vector<int> adj[(int)1e6], city((int)1e6), peepsInPath((int)1e6), numOfChild((int)1e6);
void dfs(int u, int parent){
for(int v : adj[u]){
if(v == parent) continue;
dfs(v, u);
numOfChild[u] += numOfChild[v]; peepsInPath[u] = max(peepsInPath[u], peepsInPath[v]);
}
peepsInPath[u] = max(peepsInPath[u], peeps - numOfChild[u] - city[u]); numOfChild[u] += city[u];
}
int LocateCentre(int n, int *p, int *s, int *d){
for(int i = 0; i < n; i++){
peeps += p[i]; city[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);
int ans = -1, cong = INT_MAX;
for(int i = 0; i < n; i++){
if(peepsInPath[i] < cong){
ans = i; cong = peepsInPath[i];
}
}
return ans;
}
