This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include<bits/stdc++.h>
#define ll long long
#define endl "\n"
#define fi first
#define se second
#define pb push_back
#define pll pair<long long, long long>
#define loop(i,n) for(int i=1;i<=n;i++)
#define loop0(i,n) for(int i=0;i<n;i++)
using namespace std;
//pbds template
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
template <class T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;
void solve(){
	ll n;
	cin >> n;
	ll a[n+5] = {0};
	ll b[n+5] = {0};
	vector<pair<pair<ll,ll>,ll>> v;
	map<ll,vector<ll>> m;
	for(int i=1;i<=n;i++){
		cin >> a[i];
	}
	for(int i=1;i<=n;i++){
		cin >> b[i];
	}
	ll ans = 0;
	for(int i=1;i<=n;i++){
		v.pb({{a[i],b[i]},i});
	}
	sort(v.begin(),v.end());
//	for(auto i:v){
//		cout << i.fi.fi << ' ' << i.fi.se << ' ' << i.se << endl;
//	}
	ordered_set<ll> o_set;
	for(auto i:v){
//		cout << i.fi.fi << ' ' << i.fi.se << ' ' << m[i.fi.fi].size() << endl;
		stack<ll> buffer;
		if(m.count(i.fi.fi)){
			for(auto j:m[i.fi.fi]){
				ll idx1 = o_set.order_of_key(i.se);
				ll idx2 = o_set.order_of_key(j);
//				cout << idx1 << ' ' << idx2 << endl;
				if(idx1==idx2){
					ans++;
					buffer.push(j);
				}
			}
			while(!buffer.empty()){
				o_set.insert(buffer.top());
				buffer.pop();
			}
		}
		if(i.fi.fi==i.fi.se){
			ans++;
			o_set.insert(i.se);
		}
		else{
			m[i.fi.se].pb(i.se);
		}
	}
	cout << ans << endl;
}
int main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	int tc = 1;
//	cin >> tc;
	while(tc--){
	   solve();
	}
}
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