#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
#define first X
#define second Y
#define eb emplace_back
#define ALL(i) i.begin(),i.end()
#define SZ(i) int(i.size())
#ifdef tmd
#define debug(...) fprintf(stderr,"#%d-(%s)=",__LINE__,#__VA_ARGS__);_do(__VA_ARGS__);
template<typename T> void _do (T &&x) {cerr<<x<<endl;}
template<typename T, typename ...S> void _do(T &&x, S &&...y) {cerr<<x<<",";_do(y...);}
template<typename IT> ostream &__printRng (ostream& os, IT bg, IT ed) {
for (IT it=bg; it!=ed; it++) {
if (it == bg) os << "{" << *it;
else os << "," << *it;
}
return os << "}";
}
template<typename T> ostream &operator << (ostream& os, const vector<T> &vec) {
return __printRng(os,ALL(vec));
}
#else
#define debug(...)
#endif
#include "friend.h"
// Find out best sample
const int MAXN = 1003;
vector<int> edge[MAXN];
void add_edge (int u, int v) {
edge[u].eb(v);
edge[v].eb(u);
}
bool vis[MAXN];
vector<int> xs, ys;
void dfs (int nd, int c) {
if (c) xs.eb(nd);
else ys.eb(nd);
vis[nd] = true;
for (auto v : edge[nd]) {
if (!vis[v]) {
dfs(v, c^1);
}
}
}
int yp[MAXN];
bool mat (int nd) {
if (vis[nd]) return false;
vis[nd] = true;
for (int u : edge[nd]) {
if (yp[u] == -1 || mat(yp[u])) {
yp[u] = nd;
return true;
}
}
return false;
}
int findSample(int n,int confidence[],int host[],int p[]){
bool fc = false;
for (int i=1; i<n; i++) {
if (p[i] == 0) {
add_edge(i, host[i]);
} else if (p[i] == 1) {
for (auto v : edge[host[i]]) {
add_edge(v, i);
}
} else {
for (auto v : edge[host[i]]) {
add_edge(v, i);
}
add_edge(i, host[i]);
fc = true;
}
}
for (int i=0; i<n; i++) {
if (!vis[i]) {
dfs(i, 0);
}
}
memset(vis, 0, sizeof(vis));
memset(yp, -1, sizeof(yp));
int ans = 0;
for (int i : xs) {
if (!vis[i]) {
memset(vis, 0, sizeof(vis));
ans += mat(i);
}
}
return n - ans;
}
