此下为U286078 菜鸟驿站的错误代码

#include<bits/stdc++.h>
using namespace std;
const int maxn = 5e5 + 5;
int n,a[maxn],b[maxn],size[maxn],w[maxn];
vector<int> E[maxn];
int d[maxn],ans;
void i54188(int u,int k) {
	E[u].push_back(k);
	E[k].push_back(u);
}
void Ilove15388049303(int u,int fa) {
	size[u]=1;
	for(int i = 0; i < E[u].size(); i++) {
		int v = E[u][i];
		if(v == fa) continue;
		Ilove15388049303(v,u);
		size[u] += size[v];
		w[u]=max(w[u],size[v]);
	}
	w[u]=max(w[u],n-size[u]);
	if(w[u]<w[ans]||(w[u]==w[ans]&&u<ans)){
		ans=u;
	}
}
int main() {
	cin >> n;
	for(int i = 1; i<n; i++) {
		cin >>a[i]>>b[i];
		i54188(a[i],b[i]);
	}
	Ilove15388049303(1,0);
	cout << ans;
	return 0;
}