#include <bits/stdc++.h>
using namespace std;
struct emp {
  int val, num;
  bool le, ri;
} tree[4 * 800005], O;
long long n, lef[800005], rig[800005], lazy[4 * 800005], q;
vector<long long> v;
void propagate(int s, int e, int x) {
  if (s != e) {
    lazy[2 * x] += lazy[x];
    lazy[2 * x + 1] += lazy[x];
  }
  tree[x].num += (e - s + 1) * lazy[x];
  lazy[x] = 0;
  return;
}
void update(int s, int e, int x, int l, int r) {
  int m = s + e >> 1;
  propagate(s, e, x);
  if (r < s || e < l) return;
  if (l <= s && e <= r) {
    lazy[x]++;
    propagate(s, e, x);
    return;
  }
  update(s, m, 2 * x, l, r);
  update(m + 1, e, 2 * x + 1, l, r);
  tree[x].num = tree[2 * x].num + tree[2 * x + 1].num;
  return;
}
void init(int s, int e, int x) {
  int m = s + e >> 1;
  propagate(s, e, x);
  if (s == e) {
    tree[x].le = tree[x].ri = tree[x].val = (tree[x].num <= 1);
    return;
  }
  init(s, m, 2 * x);
  init(m + 1, e, 2 * x + 1);
  tree[x].le = tree[2 * x].le;
  tree[x].ri = tree[2 * x + 1].ri;
  tree[x].val = tree[2 * x].val + tree[2 * x + 1].val -
                (tree[2 * x].ri && tree[2 * x + 1].le);
  tree[x].num = tree[2 * x].num + tree[2 * x + 1].num;
  return;
}
emp read(int s, int e, int x, int l, int r) {
  int m = s + e >> 1;
  propagate(s, e, x);
  if (r < s || e < l) return O;
  if (l <= s && e <= r) return tree[x];
  emp p, p1 = read(s, m, 2 * x, l, r), p2 = read(m + 1, e, 2 * x + 1, l, r);
  p.val = p1.val + p2.val - (p1.ri && p2.le);
  p.le = p1.le;
  p.ri = p2.ri;
  p.num = p1.num + p2.num;
  return p;
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cin >> q;
  while (q--) {
    cin >> n;
    for (int i = 0; i < n; i++) {
      cin >> lef[i] >> rig[i];
      v.push_back(lef[i]);
      v.push_back(rig[i]);
    }
    sort(v.begin(), v.end());
    v.erase(unique(v.begin(), v.end()), v.end());
    int sz = 2 * v.size() - 1;
    for (int i = 0; i < n; i++) {
      lef[i] = 2 * (lower_bound(v.begin(), v.end(), lef[i]) - v.begin());
      rig[i] = 2 * (lower_bound(v.begin(), v.end(), rig[i]) - v.begin());
      update(0, sz - 1, 1, lef[i], rig[i]);
    }
    init(0, sz - 1, 1);
    int maxn = -1e9;
    for (int i = 0; i < n; i++) {
      maxn = max(maxn, read(0, sz - 1, 1, lef[i], rig[i]).val -
                           read(0, sz - 1, 1, lef[i], lef[i]).val -
                           read(0, sz - 1, 1, rig[i], rig[i]).val);
    }
    update(0, sz - 1, 1, 0, sz - 1);
    init(0, sz - 1, 1);
    cout << maxn + read(0, sz - 1, 1, 0, sz - 1).val + 1 << "\n";
    for (int i = 0; i < 4 * sz; i++) {
      tree[i] = O;
      lazy[i] = 0;
    }
    v.clear();
  }
  return 0;
}
