#include <bits/stdc++.h>
using namespace std;
int _gcd(int a, int b) { return (b == 0 ? a : _gcd(b, a % b)); }
bool cmp(int a, int b) { return a > b; }
int dx[3] = {1, 0, 1};
int dy[3] = {0, 1, 1};
bool check(string a, string b, string c) {
  if (a == b && b == c) return true;
  if (a > b) swap(a, b);
  if (b > c) swap(b, c);
  if (a > b) swap(a, b);
  if (a[1] == b[1] && b[1] == c[1]) {
    if (a[0] + 1 == b[0] && b[0] + 1 == c[0]) return true;
  }
  return false;
}
long long int ncr(long long int n, long long int k) {
  long long int res = 1;
  for (long long int i = n; i > n - k; --i) {
    res *= i;
  }
  for (long long int i = 2; i <= k; ++i) {
    res /= i;
  }
  return res;
}
const int mod = 1e9 + 7;
void solve() {
  long long int n;
  cin >> n;
  vector<long long int> v(n + 1, 0);
  for (long long int i = 1; i <= n; ++i) {
    cin >> v[i];
  }
  vector<long long int> ans;
  for (long long int i = 1; i <= n; ++i) {
    if (i == 1 || i == n || (v[i - 1] < v[i]) != (v[i] < v[i + 1]))
      ans.push_back(v[i]);
  }
  cout << ans.size() << endl;
  for (auto x : ans) {
    cout << x << " ";
  }
  cout << endl;
}
int main() {
  ios_base::sync_with_stdio(false), cin.tie(NULL), cout.tie(NULL);
  long long int t;
  cin >> t;
  while (t--) {
    solve();
  }
  return 0;
}
