/*
 *   Copyright (c) 2025 Emon Thakur
 *   All rights reserved.
 */
#include<bits/stdc++.h>
using namespace std;
using ll=long long;

struct SGT{
    vector<ll> sg;
    SGT(int n) {sg.resize(n*4+10); }
   
    void update(int node,int start,int end,int ind,ll val)
    {
        if(start==end)
        {
            sg[node] = max(sg[node] , val);
            return;
        }
        int mid = (start + end)/2;
        if(ind <= mid) update(node*2,start,mid,ind,val);
        else update(node*2+1,mid+1,end,ind,val);
        sg[node] = max(sg[node*2] , sg[node*2]+1);
    }

    ll query(int node,int start,int end,int l,int r)
    {
        if(l>end || r<start) return 0;
        if(l<=start && r>=end) return sg[node];
        int mid = (start+end)/2;
        return max(query(node*2,start,mid,l,r) , query(node*2+1,mid+1,end,l,r));
    }
};

ll calc(int ind,int n,vector<int>&a,vector<int>&b)
{
    ll ans = 0;
    SGT sgt(n);

    for(int i=ind;i<n;i++)
    {
        ll pmax =(a[i]==1)? 0 : sgt.query(1,1,n,0,a[i]-1);
        ans = max(ans , pmax+b[i]);
        sgt.update(1,1,n,a[i],ans);
    }
    return ans;
}

void main2(int tc)
{
    // string outp = "output"+to_string(tc)+".txt";
    // string inp = "input"+to_string(tc)+".txt";
    // ofstream file(outp);
    // freopen(inp.c_str(),"r",stdin);
    ios::sync_with_stdio(false); cin.tie(nullptr);
    int t; cin >> t; while(t--)
    {
        int n; cin >> n;
        vector<int> a(n),b(n);
        for(int i=0;i<n;i++) cin >> a[i];
        for(int i=0;i<n;i++) cin >> b[i];
        
        ll mxans = calc(0,n,a,b);

        int lo=0,hi=n-1,mid,ind=0;
        while(lo<=hi)
        {
            mid = (lo+hi)/2;
            if(calc(mid,n,a,b) == mxans)
            {
                ind = mid;
                lo = mid+1;
            }else hi = mid-1;
        }
        cout<<n-ind<<'\n';
        //file<<n-ind<<'\n';
    }
}

int main()
{
    main2(0);
    //for(int i=0;i<100;i++) main2(i);
}