#include <bits/stdc++.h>
const int N = 200010;
const long long INF = 1ll << 60;
const int inf = 0x3f3f3f3f;
const long long mod = 1e9 + 7;
class Discretization {
 public:
  Discretization() { vec_.clear(); }
  void Init() { vec_.clear(); }
  void Add(int x) { vec_.push_back(x); }
  void Build() {
    std::sort(vec_.begin(), vec_.end());
    vec_.erase(std::unique(vec_.begin(), vec_.end()), vec_.end());
  }
  int Id(int x) {
    auto y = std::lower_bound(vec_.begin(), vec_.end(), x);
    if (y == vec_.end() || *y != x) {
      return -1;
    } else {
      return y - vec_.begin() + 1;
    }
  }
  int IdLeq(int x) {
    auto y = std::upper_bound(vec_.begin(), vec_.end(), x);
    if (y == vec_.begin()) {
      return 0;
    } else {
      --y;
      return y - vec_.begin() + 1;
    }
  }
  int IdGeq(int x) {
    auto y = std::lower_bound(vec_.begin(), vec_.end(), x);
    if (y == vec_.end()) {
      return vec_.size() + 1;
    } else {
      return y - vec_.begin() + 1;
    }
  }
  int Size() { return vec_.size(); }
  int Value(int id) { return vec_[id - 1]; }

 private:
  std::vector<int> vec_;
} disc;
int t;
int n, m;
int a[N];
int b[N];
std::vector<int> vec[N << 2][2];
std::set<int> se;
std::vector<int> why[N];
int init = 0;
bool left[N], right[N];
int main() {
  scanf("%d", &t);
  while (t--) {
    scanf("%d", &n);
    disc.Init();
    for (int i = 1; i <= n; ++i) {
      scanf("%d%d", &a[i], &b[i]);
      disc.Add(a[i]);
      disc.Add(b[i]);
    }
    disc.Build();
    for (int i = 1; i <= 2 * n; ++i) vec[i][0].clear(), vec[i][1].clear();
    for (int i = 1; i <= n; ++i) {
      vec[disc.Id(a[i])][0].push_back(i);
      vec[disc.Id(b[i])][1].push_back(i);
      why[i].clear();
      left[i] = right[i] = false;
    }
    se.clear();
    int id_before, id_after;
    init = 0;
    for (int i = 1; i <= disc.Size(); ++i) {
      int before = se.size();
      if (before == 1) id_before = *se.begin();
      for (size_t j = 0; j < vec[i][0].size(); ++j) {
        se.insert(vec[i][0][j]);
      }
      int after = se.size();
      if (before == 1 && after > 1) why[id_before].push_back(1);
      if (before == 0 && after == 1) left[*se.begin()] = true;
      before = se.size();
      if (before == 1) id_before = *se.begin();
      for (size_t j = 0; j < vec[i][1].size(); ++j) {
        se.erase(vec[i][1][j]);
      }
      after = se.size();
      if (after == 1) id_after = *se.begin();
      if (before > 1 && after == 1) why[id_after].push_back(-1);
      if (before == 1 && after == 0) right[id_before] = true;
      if (!se.size()) ++init;
    }
    int ans = 0;
    for (int i = 1; i <= n; ++i) {
      if (left[i] && right[i] && !why[i].size()) {
        ans = std::max(ans, init - 1);
      } else {
        int cnt = 0;
        int last = -2;
        for (size_t j = 0; j < why[i].size(); ++j) {
          if (last == -1 && why[i][j] == 1) ++cnt;
          last = why[i][j];
        }
        ans = std::max(ans, init + cnt);
      }
    }
    printf("%d\n", ans);
  }
  return 0;
}
