#include "bits/stdc++.h"
using namespace std;

typedef long long ll;

#define deb(...) logger(#__VA_ARGS__, __VA_ARGS__)
template<typename ...Args>
void logger(string vars, Args&&... values) {
  cout << vars << " = ";
  string delim = "";
  (..., (cout << delim << values, delim = ", "));
  cout << '\n';
}

void solve() {
  int n;
  cin >> n;
  vector<int> a(n);
  for (int &x : a) cin >> x, --x;
  vector<int> w(n);
  for (int i = 0; i < n; ++i) {
    int x;
    cin >> x;
    --x;
    w[x] = i;
  }
  int mx = 0;
  int ans = 0;
  for (int x : a) {
    if (mx > w[x]) ++ans;
    mx = max(mx, w[x]);
  }
  cout << ans << '\n';
}

int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  int t = 1;
  cin >> t;
  while(t--) {
    solve();
  }
}