// #pragma optimize ("g",on)
// #pragma GCC optimize ("inline")
// #pragma GCC optimize ("Ofast")
// #pragma GCC optimize ("unroll-loops")
// #pragma GCC optimize ("03")
#include <bits/stdc++.h>
#define pb push_back
#define SS ios_base::sync_with_stdio(0);cin.tie(nullptr);cout.tie(nullptr);
#define int long long
#define all(v) v.begin(),v.end()
using namespace std;
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
const int N = 2e5 + 1, inf = 1e9, mod = 998244353;
int n;
int a[N], b[N];
void solve(){
cin >> n;
vector<int> v;
for(int i = 1; i <= n; i++){
cin >> a[i];
v.push_back(a[i]);
}
for(int i = 1; i <= n; i++){
cin >> b[i];
v.push_back(b[i]);
}
sort(all(v));
v.erase(unique(all(v)), v.end());
for(int i = 1; i <= n; i++){
a[i] = lower_bound(all(v), a[i]) - v.begin() + 1;
b[i] = lower_bound(all(v), b[i]) - v.begin() + 1;
}
int dp[n + 1] = {};
int r = b[1];
for(int i = 2; i <= n; i++){
if(r != b[i]){
r = -1;
break;
}
}
if(r >= 0){
int last = 0, ans = 0, ok = 0;
for(int i = 1; i <= n; i++){
if(r < a[i]){
ok = 0;
last = i;
}
else if(r == a[i]){
ok = 1;
ans += i - last;
}
else if(ok) ans++;
}
cout << ans;
return;
}
int ans = 0;
for(int i = 1; i <= n; i++){
int cnt = 0;
for(int j = i; j >= 1; j--){
if(b[j] == a[i]) cnt++;
dp[i] = max(dp[i], dp[j - 1] + cnt);
ans = max(ans, dp[i]);
}
}
cout << ans;
}
signed main(){
SS
// freopen("trains.in", "r", stdin);
// freopen("trains.out", "w", stdout);
int t = 1;
// cin >> t;
while(t--){
solve();
}
}
