#include "catdog.h"
#include <bits/stdc++.h>
using namespace std;
const int MAXN = 100005;
const int inf = 1e9;
int n, a[MAXN];
vector<int> gph[MAXN];
int dp[MAXN][3], par[MAXN];
void cons(int v){
memset(dp[v], 0, sizeof(dp[v]));
for(auto &i : gph[v]){
dp[v][0] += min({dp[i][0] + (a[i] ? inf : 0), dp[i][1] + 1 + (a[i] == 2 ? inf : 0), dp[i][2] + 1 + (a[i] == 1 ? inf : 0)});
dp[v][1] += min({dp[i][0] + (a[i] ? inf : 0), dp[i][1] + (a[i] == 2 ? inf : 0), dp[i][2] + 1 + (a[i] == 1 ? inf : 0)});
dp[v][2] += min({dp[i][0] + (a[i] ? inf : 0), dp[i][1] + 1 + (a[i] == 2 ? inf : 0), dp[i][2] + (a[i] == 1 ? inf : 0)});
}
}
int cat(int v) {
a[v] = 1;
while(v){
cons(v);
v = par[v];
}
if(a[1]) return dp[1][a[1]];
return min({dp[1][0], dp[1][1], dp[1][2]});
}
int dog(int v) {
a[v] = 2;
while(v){
cons(v);
v = par[v];
}
if(a[1]) return dp[1][a[1]];
return min({dp[1][0], dp[1][1], dp[1][2]});
}
int neighbor(int v) {
a[v] = 0;
while(v){
cons(v);
v = par[v];
}
if(a[1]) return dp[1][a[1]];
return min({dp[1][0], dp[1][1], dp[1][2]});
}
void dfs(int x){
for(auto &i : gph[x]){
gph[i].erase(find(gph[i].begin(), gph[i].end(), x));
par[i] = x;
dfs(i);
}
cons(x);
}
void initialize(int N, std::vector<int> A, std::vector<int> B) {
n = N;
for(int i=0; i<n-1; i++){
gph[A[i]].push_back(B[i]);
gph[B[i]].push_back(A[i]);
}
dfs(1);
}
