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# include <bits/stdc++.h>
using namespace std ;
const int N = 1000010 , M = N < < 1 ;
# define int long long
# define endl "\n"
int n , id ;
// 链式前向星
int e [ M ] , h [ N ] , idx , w [ M ] , ne [ M ] ;
void add ( int a , int b , int c = 0 ) {
e [ idx ] = b , ne [ idx ] = h [ a ] , w [ idx ] = c , h [ a ] = idx + + ;
}
int ans ;
int f [ N ] , dep [ N ] , size [ N ] ;
void dfs1 ( int u , int fa ) {
size [ u ] = 1 ;
dep [ u ] = dep [ fa ] + 1 ;
for ( int i = h [ u ] ; ~ i ; i = ne [ i ] ) {
int v = e [ i ] ;
if ( v = = fa ) continue ;
dfs1 ( v , u ) ;
size [ u ] + = size [ v ] ;
}
}
void dfs2 ( int u , int fa ) {
for ( int i = h [ u ] ; ~ i ; i = ne [ i ] ) {
int v = e [ i ] ;
if ( v = = fa ) continue ;
f [ v ] = f [ u ] + n - 2 * size [ v ] ;
dfs2 ( v , u ) ;
}
}
signed main ( ) {
memset ( h , - 1 , sizeof h ) ;
cin > > n ;
for ( int i = 1 ; i < n ; i + + ) { // n-1条边
int a , b ;
cin > > a > > b ;
add ( a , b ) , add ( b , a ) ; // 换根DP，
}
// 1、第一次dfs,找出：
dfs1 ( 1 , 0 ) ;
// 2、换根
for ( int i = 1 ; i < = n ; i + + ) f [ 1 ] + = dep [ i ] ;
dfs2 ( 1 , 0 ) ;
// 3、找答案
for ( int i = 1 ; i < = n ; i + + )
if ( ans < f [ i ] ) ans = f [ i ] , id = i ;
cout < < id < < endl ;
}
