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

template <class T> struct SegmentTreeIterative {
  int n = 1;
  vector<T> st;
  SegmentTreeIterative() {}
  SegmentTreeIterative(int n) { Initial(n); }
  SegmentTreeIterative(vector<int>& a) {
    Initial((int)a.size() - 1);
    Build(a);
  }
  void Initial(int _n) {
    n = _n;
    int tree_size = 1;
    while (tree_size <= n) tree_size *= 2;
    st.resize(tree_size * 2);
  }
  T neutral = 0;
  T Merge(T& a, T& b) {
    return max(a, b);
  }
  void Build(vector<int>& a) {
    for (int i = 1; i <= n; ++i) {
      st[n + i] = a[i];
    }
    for (int u = n - 1; u > 0; --u) {
      st[u] = Merge(st[u << 1], st[u << 1 | 1]);
    }
  }
  void Update(int idx, T val) {
    st[idx += n] = val;
    for (idx /= 2; idx; idx /= 2) {
      st[idx] = Merge(st[idx << 1], st[idx << 1 | 1]);
    }
  }
  T Query(int l, int r) {
    T res = neutral;
    for (l += n, r += n + 1; l < r; l >>= 1, r >>= 1) {
      if (l & 1) res = Merge(res, st[l++]);
      if (r & 1) res = Merge(res, st[--r]);
    }
    return res;
  }
};

void solve() {
  int n;
  cin >> n;
  vector<int> a(n + 1);
  for (int i = 1; i <= n; i++) {
    cin >> a[i];
  }
  vector<int> b(n + 1);
  for (int i = 1; i <= n; i++) {
    cin >> b[i];
  }
  SegmentTreeIterative<int64_t> sg(n + 9);
  vector<int64_t> mx(n + 1);
  int64_t gMx = 0;
  for (int i = n; i > 0; i--) {
    mx[i] = sg.Query(a[i] + 1, n + 1) + b[i];
    if (sg.Query(a[i], a[i]) < mx[i]) {
      sg.Update(a[i], mx[i]);
    }
    gMx = max(gMx, mx[i]);
  }
  int i = n;
  while (i > 0 && gMx != mx[i]) i--;
  cout << n - i + 1 << '\n';
}

int main() {
  ios_base::sync_with_stdio(0), cin.tie(0);
  int t = 1;
  cin >> t;
  for (int i = 1; i <= t; i++) {
    solve();
  }
  return 0;
}