1.4t6

include<bits/stdc++.h>

define endl '\n'

using namespace std;
typedef long long ll;
typedef pair<ll,ll> pll;
vector v;
vector tree;
unordered_map<ll,pll> mp;
ll count(ll x){
if(x-1)return 0;
ll l=mp[x].first;
ll r=mp[x].second;
tree[x]=count(l)+count(r)+1;
return tree[x];
}
bool mirror(ll x,ll y){
if(x-1&&y-1)return true;
if(x-1||y==-1)return false;
if(v[x]!=v[y])return false;
return mirror(mp[x].first,mp[y].second)&&mirror(mp[x].second,mp[y].first);
}
int main(){
ios::sync_with_stdio(false);cin.tie(0);
ll n;
cin>>n;
tree.resize(n+1);
v.resize(n+1);
for(ll i=1;i<=n;i++)cin>>v[i];
for(ll i=1;i<=n;i++){
cin>>mp[i].first>>mp[i].second;
}
ll ans=0;
count(1);
for(ll i=1;i<=n;i++){
if(mirror(i,i))ans=max(ans,tree[i]);
}
cout<<ans<<endl;
return 0;
}