func_code_string: #include <bits/stdc++.h>   using namespace std;   long long int binary_exp(long long int a, long long int n) {     long long int i = 1;     while (n > 0) {       if (n % 2 == 1) i = (i * a) % 1000000007;       a = (a * a) % 1000000007;       n /= 2;     }     return i;   }   long long int IsPrime(long long int n) {     if (n == 0 || n == 1) return n;     if (n % 2 == 0) return (long long int)2;     if (n % 3 == 0)       return (long long int)3;     else {       for (long long int i = 5; i * i <= n; i += 6) {         if (n % i == 0) return i;         if (n % (i + 2) == 0) return (i + 2);       }       return n;     }   }   void solve() {     int n, i, j, k, a, b, mex = 1, ans = 0;     cin >> n;     int ind[n + 1];     bool vis[n + 1];     memset(vis, false, sizeof(vis));     for (i = 1; i <= n; i++) {       cin >> k;       ind[k] = i;     }     for (i = 1; i <= n; i++) {       cin >> k;       vis[ind[k]] = true;       while (mex <= n && vis[mex]) mex++;       if (ind[k] > mex) ans++;     }     cout << ans;   }   int main() {     ios_base::sync_with_stdio(false), cin.tie(0), cout.tie(0);     srand(time(NULL));     ;     int t = 1;     while (t--) solve();   }   