#include<iostream>

 #include<cstdio>

 #include<cmath>

 #include<algorithm>

 #include<queue>

 #include<cstring>

 #define PAU putchar(' ')

 #define ENT putchar('\n')

 using namespace std;

 const int maxn=+;

 struct tedge{int x,y,next;}adj[maxn<<];int ms=,fch[maxn];

 void addedge(int u,int v){

     adj[++ms]=(tedge){u,v,fch[u]};fch[u]=ms;

     adj[++ms]=(tedge){v,u,fch[v]};fch[v]=ms;

     return;

 }

 int s[maxn],f[maxn],cg,n;

 void findcg(int u,int fa){

     s[u]=;int mxs=;

     for(int i=fch[u];i;i=adj[i].next){

         int v=adj[i].y;if(v!=fa){

             findcg(v,u);

             s[u]+=s[v];

             mxs=max(mxs,s[v]);

         }

     } f[u]=max(n-s[u],mxs);

     if(f[u]<f[cg]) cg=u;

     else if(f[u]==f[cg]) cg=min(u,cg);return;//编号小的

 }

 inline int read(){

     int x=,sig=;char ch=getchar();

     while(!isdigit(ch)){if(ch=='-')sig=-;ch=getchar();}

     while(isdigit(ch))x=*x+ch-'',ch=getchar();

     return x*=sig;

 }

 inline void write(int x){

     if(x==){putchar('');return;}if(x<)putchar('-'),x=-x;

     int len=,buf[];while(x)buf[len++]=x%,x/=;

     for(int i=len-;i>=;i--)putchar(buf[i]+'');return;

 }

 void init(){

     n=read();f[cg=]=n;

     for(int i=;i<n;i++) addedge(read(),read());

     findcg(,);

     write(cg);

     return;

 }

 void work(){

     return;

 }

 void print(){

     return;

 }

 int main(){init();work();print();return ;}

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