#define __MAXSIZE__ 100002
#include "friend.h"
#include <bits/stdc++.h>
using namespace std;
#define sp " "
#define endl "\n"
#define pb push_back
#define pii pair<int, int>
#define st first
#define nd second
#define mid (l + r) / 2
#define LL node * 2
#define RR node * 2 + 1
#define fileio() freopen("input.txt", "r", stdin), freopen("output.txt", "w", stdout)
#define fastio() cin.tie(0), ios_base::sync_with_stdio(0)
#define ll long long
#define MAXN 200005
const int modulo = 1e9+7;
const ll INF = 2e18 + 7;
vector<int> adj[MAXN];
void dfs(int node, int &a, int &b){
a++;
for (auto i : adj[node]){
dfs(i, b, a);
}
}
// Find out best sample
int findSample(int n,int confidence[],int host[],int protocol[]){
int ans=0;
vector<int> roots;
roots.pb(0);
for (int i = 1; i < n; i++){
if (protocol[i] == 0) //I am your friend
adj[host[i]].pb(i);
else if (adj[host[i]].empty()){
roots.pb(i);
}
else adj[adj[host[i]].front()].pb(i);
}
for (auto i : roots){
int a = 0, b = 0;
dfs(i, a, b);
ans += max(a, b);
}
return ans;
}
/*
// Confidence
int confidence[__MAXSIZE__];
// Host
int host[__MAXSIZE__];
// Protocol
int protocol[__MAXSIZE__];
// Main
int main(void)
{
fileio();
int n,i;
// Number of people
assert(scanf("%d",&n)==1);
// Confidence
for(i=0;i<n;i++)
assert(scanf("%d",&confidence[i])==1);
// Host and Protocol
for(i=1;i<n;i++)
assert(scanf("%d %d",&host[i],&protocol[i])==2);
// Answer
printf("%d\n",findSample(n,confidence,host,protocol));
return 0;
}
*/
