#include <bits/stdc++.h>
using namespace std;
const int N = 6e5 + 9, M = 21;
int T, n, t, tn, ta[N], maxl[N], maxr[N], mrk[N], nxt[N][M];
vector<int> pos, ans;
struct node {
  int l, r;
} a[N];
struct node {
  int l, r, mid, s;
} p[N << 2];
inline bool inside(int l, int r) { return l <= r && maxl[r] >= l; }
inline bool outside(int l, int r) { return l > r || maxr[l] >= r; }
void build(int u, int l, int r) {
  p[u].l = l, p[u].r = r, p[u].mid = (l + r) >> 1, p[u].s = 0;
  if (l == r) return;
  build(u << 1, l, p[u].mid);
  build(u << 1 | 1, p[u].mid + 1, r);
}
void modify(int u, int k, int x) {
  if (p[u].l == p[u].r) {
    p[u].s += x;
    return;
  }
  modify(k <= p[u].mid ? u << 1 : u << 1 | 1, k, x);
  p[u].s = p[u << 1].s + p[u << 1 | 1].s;
}
int query(int u, int l, int r) {
  if (p[u].l == l && p[u].r == r) return p[u].s;
  if (r <= p[u].mid) return query(u << 1, l, r);
  if (l > p[u].mid) return query(u << 1 | 1, l, r);
  return query(u << 1, l, p[u].mid) + query(u << 1 | 1, p[u].mid + 1, r);
}
int main() {
#ifdef memset0
  freopen("1.in", "r", stdin);
#endif
  cin.tie(0)->sync_with_stdio(0);
  for (cin >> T; T--;) {
    t = tn = 0, ans.clear(), pos.clear();
    cin >> n;
    ta[++tn] = 1e9 + 10, ta[++tn] = -1e9 - 10;
    for (int i = 1; i <= n; i++) {
      cin >> a[i].l, ta[++tn] = a[i].l;
      cin >> a[i].r, ta[++tn] = a[i].r;
      ta[++tn] = a[i].l - 1, ta[++tn] = a[i].l + 1;
      ta[++tn] = a[i].r - 1, ta[++tn] = a[i].r + 1;
    }
    sort(ta + 1, ta + tn + 1);
    tn = unique(ta + 1, ta + tn + 1) - ta - 1;
    for (int i = 1; i <= n; i++) {
      a[i].l = lower_bound(ta + 1, ta + tn + 1, a[i].l) - ta;
      a[i].r = lower_bound(ta + 1, ta + tn + 1, a[i].r) - ta;
    }
    memset(maxl + 1, 0, tn << 2);
    memset(maxr + 1, 0, tn << 2);
    for (int i = 1; i <= n; i++) {
      maxl[a[i].r] = max(maxl[a[i].r], a[i].l);
      maxr[a[i].l] = max(maxr[a[i].l], a[i].r);
    }
    for (int i = 1; i <= tn; i++) {
      maxl[i] = max(maxl[i - 1], maxl[i]);
      maxr[i] = max(maxr[i - 1], maxr[i]);
    }
    sort(a + 1, a + n + 1, [](const node &a, const node &b) { return a.r == b.r ? a.l < b.l : a.r < b.r; });
    build(1, 1, tn);
    for (int i = 1; i <= n; i++)
      if (!query(1, a[i].l, a[i].r)) {
        modify(1, a[i].r, 1);
        ans.push_back(a[i].r);
      }
    for (int i = 1; i <= n; i++) {
      t = max(t, query(1, a[i].l, a[i].r));
    }
    if (t > 1) {
      memset(mrk + 1, 0, tn);
      pos.push_back(tn), mrk[tn] = 1;
      for (int i = 0; i < M; i++) nxt[tn][i] = tn;
      for (int i = tn - 1, j, l, r, mid, s, k; i >= 1; i--) {
        l = 0, r = pos.size() - 1, nxt[i][0] = -1;
        while (l <= r) {
          mid = (l + r) >> 1;
          if (!inside(i + 1, pos[mid] - 1)) {
            nxt[i][0] = pos[mid];
            r = mid - 1;
          } else {
            l = mid + 1;
          }
        }
        if (!~nxt[i][0]) continue;
        for (j = nxt[i][0], k = M - 1, s = t - 2; k >= 0; k--) {
          if ((s >> k) & 1) j = nxt[j][k];
        }
        if (outside(i, j)) continue;
        pos.push_back(i), mrk[i] = 1;
        for (int j = 1; j < M; j++) {
          nxt[i][j] = nxt[nxt[i][j - 1]][j - 1];
        }
      }
      int minl = tn;
      for (int i = 1; i <= n; i++) minl = min(minl, a[i].l);
      if (mrk[minl - 1]) {
        --t, ans.clear();
        int u = minl - 1;
        while (u != tn) ans.push_back(u), u = nxt[u][0];
        if (ans.front() == 1) ans.erase(ans.begin());
      }
    }
    cout << t << ' ' << ans.size() << ' ';
    for (int i = 0; i < ans.size(); i++) {
      cout << ta[ans[i]] << " \n"[i + 1 == ans.size()];
    }
  }
}

answer.code:9:8: error: redefinition of ‘struct node’
    9 | struct node {
      |        ^~~~
answer.code:6:8: note: previous definition of ‘struct node’
    6 | struct node {
      |        ^~~~
answer.code: In function ‘void build(int, int, int)’:
answer.code:15:8: error: request for member ‘l’ in ‘p[u]’, which is of non-class type ‘int’
   15 |   p[u].l = l, p[u].r = r, p[u].mid = (l + r) >> 1, p[u].s = 0;
      |        ^
answer.code:15:20: error: request for member ‘r’ in ‘p[u]’, which is of non-class type ‘int’
   15 |   p[u].l = l, p[u].r = r, p[u].mid = (l + r) >> 1, p[u].s = 0;
      |                    ^
answer.code:15:32: error: request for member ‘mid’ in ‘p[u]’, which is of non-class type ‘int’
   15 |   p[u].l = l, p[u].r = r, p[u].mid = (l + r) >> 1, p[u].s = 0;
      |                                ^~~
answer.code:15:57: error: request for member ‘s’ in ‘p[u]’, which is of non-class type ‘int’
   15 |   p[u].l = l, p[u].r = r, p[u].mid = (l + r) >> 1, p[u].s = 0;
      |                                                         ^
answer.code:17:25: error: request for member ‘mid’ in ‘p[u]’, which is of non-class type ‘int’
   17 |   build(u << 1, l, p[u].mid);
      |                         ^~~
answer.code:18:26: error: request for member ‘mid’ in ‘p[u]’, which is of non-class type ‘int’
   18 |   build(u << 1 | 1, p[u].mid + 1, r);
      |                          ^~~
answer.code: In function ‘void modify(int, int, int)’:
answer.code:21:12: error: request for member ‘l’ in ‘p[u]’, which is of non-class type ‘int’
   21 |   if (p[u].l == p[u].r) {
      |            ^
answer.code:21:22: error: request for member ‘r’ in ‘p[u]’, which is of non-class type ‘int’
   21 |   if (p[u].l == p[u].r) {
      |                      ^
answer.code:22:10: error: request for member ‘s’ in ‘p[u]’, which is of non-class type ‘int’
   22 |     p[u].s += x;
      |          ^
answer.code:25:20: error: request for member ‘mid’ in ‘p[u]’, which is of non-class type ‘int’
   25 |   modify(k <= p[u].mid ? u << 1 : u << 1 | 1, k, x);
      |                    ^~~
answer.code:26:8: error: request for member ‘s’ in ‘p[u]’, which is of non-class type ‘int’
   26 |   p[u].s = p[u << 1].s + p[u << 1 | 1].s;
      |        ^
answer.code:26:22: error: request for member ‘s’ in ‘p[(u << 1)]’, which is of non-class type ‘int’
   26 |   p[u].s = p[u << 1].s + p[u << 1 | 1].s;
      |                      ^
answer.code:26:40: error: request for member ‘s’ in ‘p[((u << 1) | 1)]’, which is of non-class type ‘int’
   26 |   p[u].s = p[u << 1].s + p[u << 1 | 1].s;
      |                                        ^
answer.code: In function ‘int query(int, int, int)’:
answer.code:29:12: error: request for member ‘l’ in ‘p[u]’, which is of non-class type ‘int’
   29 |   if (p[u].l == l && p[u].r == r) return p[u].s;
      |            ^
answer.code:29:27: error: request for member ‘r’ in ‘p[u]’, which is of non-class type ‘int’
   29 |   if (p[u].l == l && p[u].r == r) return p[u].s;
      |                           ^
answer.code:29:47: error: request for member ‘s’ in ‘p[u]’, which is of non-class type ‘int’
   29 |   if (p[u].l == l && p[u].r == r) return p[u].s;
      |                                               ^
answer.code:30:17: error: request for member ‘mid’ in ‘p[u]’, which is of non-class type ‘int’
   30 |   if (r <= p[u].mid) return query(u << 1, l, r);
      |                 ^~~
answer.code:31:16: error: request for member ‘mid’ in ‘p[u]’, which is of non-class type ‘int’
   31 |   if (l > p[u].mid) return query(u << 1 | 1, l, r);
      |                ^~~
answer.code:32:32: error: request for member ‘mid’ in ‘p[u]’, which is of non-class type ‘int’
   32 |   return query(u << 1, l, p[u].mid) + query(u << 1 | 1, p[u].mid + 1, r);
      |                                ^~~
answer.code:32:62: error: request for member ‘mid’ in ‘p[u]’, which is of non-class type ‘int’
   32 |   return query(u << 1, l, p[u].mid) + query(u << 1 | 1, p[u].mid + 1, r);
      |                                                              ^~~