#include<bits/stdc++.h>
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;

using namespace std;

typedef vector<int>vi;
typedef pair<int, int> ii;
typedef tree<int,null_type,less<int>, rb_tree_tag, 
    tree_order_statistics_node_update> ordered_set;

#define el '\n'
#define pb push_back
#define all(a) a.begin(), a.end()
#define sz(a) (int)a.size()
#define forn(i,n) for(int i = 0; i < n;++i)
#define pb push_back
#define db(x) cerr << #x << ' ' << x << el;

void solve(){
    int n;
    cin>>n;
    vi a(n), b(n+1);
    forn(i,n)cin>>a[i];
    forn(i,n) {int num; cin>>num; b[num] = i;}

    int ans = 0;
    vi lis;
    forn(i,n){
        int x = b[a[i]];
        int it = lower_bound(all(lis), x) - lis.begin();
        if(it == sz(lis)) lis.pb(x);
        else lis[it] = x;
    }
    cout<<n-sz(lis)<<el;
}

int main(){

    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    int tt;
    cin>>tt;
    while(tt--)
        solve();
    return 0;
}