#include <bits/stdc++.h>
using namespace std;
int N, SZ, tot, ans, color[200000], cnt[200000];
set<int> S;
pair<int, int> A[200000];
vector<int> x, B, tree[1 << 19];
vector<pair<int, int>> L, R, E;
int find_(int a) {
  while (a != color[a]) a = color[a];
  return a;
}
void union_(int a, int b) {
  a = find_(a);
  b = find_(b);
  if (a == b) return;
  if (cnt[a] > cnt[b]) swap(a, b);
  color[a] = b;
  cnt[b] += cnt[a];
  B.push_back(a);
  tot--;
}
void add_edge(int s, int e, int v) {
  if (s > e) return;
  for (s += SZ, e += SZ; s <= e; s >>= 1, e >>= 1) {
    if (s & 1) tree[s++].push_back(v);
    if (~e & 1) tree[e--].push_back(v);
  }
}
void solve(int bit = 1, int s = 0, int e = SZ - 1) {
  int bsz = B.size(), m = (s + e) >> 1;
  if (N <= s) return;
  for (auto i : tree[bit]) union_(E[i].first, E[i].second);
  if (s == e) {
    ans = max(ans, tot);
    while (B.size() > bsz) {
      cnt[color[B.back()]] -= cnt[B.back()];
      color[B.back()] = B.back();
      B.pop_back();
      tot++;
    }
    return;
  }
  solve(2 * bit, s, m);
  solve(2 * bit + 1, m + 1, e);
  while (B.size() > bsz) {
    cnt[color[B.back()]] -= cnt[B.back()];
    color[B.back()] = B.back();
    B.pop_back();
    tot++;
  }
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  ((void)0);
  ((void)0);
  ((void)0);
  int T;
  for (cin >> T; T--;) {
    int i = 0, j = 0;
    cin >> N;
    tot = N - 1;
    ans = 0;
    x.clear();
    L.clear();
    R.clear(), E.clear();
    for (SZ = 1; SZ < N; SZ <<= 1)
      ;
    for (int i = 2 * SZ; --i;) tree[i].clear();
    for (int i = 0; i < N; i++) {
      cin >> A[i].first >> A[i].second;
      x.push_back(A[i].first);
      x.push_back(A[i].second);
      cnt[color[i] = i] = 1;
    }
    sort(x.begin(), x.end());
    x.resize(unique(x.begin(), x.end()) - x.begin());
    for (int i = 0; i < N; i++) {
      A[i].first = lower_bound(x.begin(), x.end(), A[i].first) - x.begin();
      A[i].second = lower_bound(x.begin(), x.end(), A[i].second) - x.begin();
      L.emplace_back(A[i].first, i);
      R.emplace_back(A[i].second, i);
    }
    sort(L.begin(), L.end());
    sort(R.begin(), R.end());
    for (int c = 0; c < x.size(); c++) {
      while (i < N && L[i].first == c) {
        auto [t, idx] = L[i++];
        if (S.size())
          E.emplace_back(min(*S.begin(), idx), max(*S.begin(), idx));
        if (S.size() > 1)
          E.emplace_back(min(*S.rbegin(), idx), max(*S.rbegin(), idx));
        S.insert(idx);
      }
      while (j < N && R[j].first == c) {
        auto [t, idx] = R[j++];
        S.erase(idx);
        if (S.size())
          E.emplace_back(min(*S.begin(), idx), max(*S.begin(), idx));
        if (S.size() > 1)
          E.emplace_back(min(*S.rbegin(), idx), max(*S.rbegin(), idx));
      }
    }
    sort(E.begin(), E.end());
    E.resize(unique(E.begin(), E.end()) - E.begin());
    for (int i = 0; i < E.size(); i++) {
      auto [a, b] = E[i];
      add_edge(0, a - 1, i);
      add_edge(a + 1, b - 1, i);
      add_edge(b + 1, N - 1, i);
    }
    solve();
    cout << ans << '\n';
  }
  return 0;
}
