text: #include <iostream>
  #include <cstdio>
  #include <algorithm>
  #include <cmath>
  #include <vector>
  #include <list>
  #include <set>
  #include <map>
  #include <queue>
  #include <stack>
  #include <cctype>
  #include <cassert>
  #include <climits>
  #include <string>
  #include <bitset>
  #include <cfloat>
  #include <random>
  #include <iomanip>
  #include <unordered_set>
  using namespace std;
  typedef long double ld;
  typedef long long int ll;
  typedef unsigned long long int ull;
  typedef vector<int> vi;
  typedef vector<char> vc;
  typedef vector<bool> vb;
  typedef vector<double> vd;
  typedef vector<string> vs;
  typedef vector<ll> vll;
  typedef vector<pair<int, int>> vpii;
  typedef vector<pair<ll, ll>> vpll;
  typedef vector<vi> vvi;
  typedef vector<vvi> vvvi;
  typedef vector<vc> vvc;
  typedef vector<vs> vvs;
  typedef vector<vll> vvll;
  typedef map<int, int> mii;
  typedef set<int> si;
  #define rep(i, n) for (ll i = 0; i < (n); ++i)
  #define rrep(i, n) for (int i = 1; i <= (n); ++i)
  #define arep(i, v) for (auto i : v)
  #define irep(it, stl) for (auto it = stl.begin(); it != stl.end(); it++)
  #define drep(i, n) for (int i = (n)-1; i >= 0; --i)
  #define fin(ans) cout << (ans) << '\n'
  #define STLL(s) strtoll(s.c_str(), NULL, 10)
  #define mp(p, q) make_pair(p, q)
  #define pb(n) push_back(n)
  #define all(a) a.begin(), a.end()
  #define rall(a) a.rbegin(), a.rend()
  #define Sort(a) sort(a.begin(), a.end())
  #define Rort(a) sort(a.rbegin(), a.rend())
  #define MATHPI acos(-1)
  #define fi first
  #define se second
  constexpr int dx[8] = {1, 0, -1, 0, 1, -1, -1, 1};
  constexpr int dy[8] = {0, 1, 0, -1, 1, 1, -1, -1};
  template <class T> inline bool chmax(T &a, T b) {
    if (a < b) {
      a = b;
      return 1;
    }
    return 0;
  }
  template <class T> inline bool chmin(T &a, T b) {
    if (a > b) {
      a = b;
      return 1;
    }
    return 0;
  }
  template <class T> inline void dump(T &v) {
    irep(i, v) { cout << *i << ((i == --v.end()) ? '\n' : ' '); }
  }
  int main() {
  
    int Q;
    cin >> Q;
    while (Q--) {
      int n;
      vi v(n);
      cin >> n;
      rep(i, n) cin >> v[i];
      vi ans{v[0], v[1]};
      for (int i = 2; i < n; i++) {
        int e2 = *(++(ans.rbegin()));
        int e1 = *(ans.rbegin());
        if (e1 == v[i])
          continue;
        else if (e2 < e1) {
          if (e1 >= v[i]) {
            ans.push_back(v[i]);
          } else
            ans.pop_back();
            ans.push_back(v[i]);
        } else {
          if (e1 <= v[i]) {
            ans.push_back(v[i]);
          } else
            ans.pop_back();
            ans.push_back(v[i]);
        }
      }
      fin(ans.size());
      dump(ans);
    }
  }
  