#include <bits/stdc++.h>
#include "friend.h"
using namespace std;
using ll = long long;
using pii = pair<int, int>;
vector<vector<int>> adj;
vector<bool> vis;
vector<int> col;
vector<int> comp;
vector<int> a;
void dfs(int u, int d=0) {
comp.push_back(u);
vis[u] = true;
col[u] = d;
for (auto v : adj[u]) {
if (vis[v]) continue;
dfs(v, 1-d);
}
}
int findSample(int n, int A[], int host[], int queries[]) {
vector<vector<int>> grid(n, vector<int>(n, 0));
adj.assign(n, {});
a.assign(n, 0);
for (int i=0; i<n; i++) {
a[i] = A[i];
}
for (int i=1; i<n; i++) {
int u = host[i];
if (queries[i] == 0) {
grid[u][i] = grid[i][u] = 1;
adj[u].push_back(i);
adj[i].push_back(u);
}
else if (queries[i] == 1) {
for (int j=0; j<i; j++) {
if (grid[u][j]) {
//cout << i << " " << j << endl;
grid[i][j] = grid[j][i] = 1;
adj[i].push_back(j);
adj[j].push_back(i);
}
}
}
else {
for (int j=0; j<i; j++) {
if (grid[u][j]) {
//cout << i << " " << j << endl;
grid[i][j] = grid[j][i] = 1;
adj[i].push_back(j);
adj[j].push_back(i);
}
}
grid[u][i] = grid[i][u] = 1;
adj[u].push_back(i);
adj[i].push_back(u);
}
}
int ans=0;
vis.assign(n, false);
col.assign(n, 0);
for (int i=0; i<n; i++) {
if (!vis[i]) {
comp.clear();
dfs(i);
int ev=0, odd=0;
for (auto u : comp) {
if (col[u]&1) odd++;
else ev++;
}
ans += max(ev, odd);
}
}
return ans;
}
