#include <bits/stdc++.h>
using namespace std;
void __print(int x) { cerr << x; }
void __print(long x) { cerr << x; }
void __print(long long x) { cerr << x; }
void __print(unsigned x) { cerr << x; }
void __print(unsigned long x) { cerr << x; }
void __print(unsigned long long x) { cerr << x; }
void __print(float x) { cerr << x; }
void __print(double x) { cerr << x; }
void __print(long double x) { cerr << x; }
void __print(char x) { cerr << '\'' << x << '\''; }
void __print(const char *x) { cerr << '\"' << x << '\"'; }
void __print(const string &x) { cerr << '\"' << x << '\"'; }
void __print(bool x) { cerr << (x ? "true" : "false"); }
template <typename T, typename V>
void __print(const pair<T, V> &x) {
  cerr << '{';
  __print(x.first);
  cerr << ',';
  __print(x.second);
  cerr << '}';
}
template <typename T>
void __print(const T &x) {
  int f = 0;
  cerr << '{';
  for (auto &i : x) cerr << (f++ ? "," : ""), __print(i);
  cerr << "}";
}
void _print() { cerr << "]\n"; }
template <typename T, typename... V>
void _print(T t, V... v) {
  __print(t);
  if (sizeof...(v)) cerr << ", ";
  _print(v...);
}
const int Nmax = 1000005;
int arr[Nmax];
bool ispeak(int i) { return arr[i] > arr[i - 1] && arr[i] > arr[i + 1]; }
bool isvalley(int i) { return arr[i] < arr[i - 1] && arr[i] < arr[i + 1]; }
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  ;
  int t, i, j, k, a, b, n, count, sum, ans;
  cin >> t;
  while (t--) {
    cin >> n;
    for (i = 1; i <= n; i++) {
      cin >> arr[i];
    }
    vector<int> ans(1, arr[1]);
    for (i = 2; i < n; i++) {
      if (ispeak(i) || isvalley(i)) {
        ans.push_back(arr[i]);
      }
    }
    ans.push_back(arr[n]);
    cout << ans.size() << "\n";
    for (auto i : ans) {
      cout << i << " ";
    }
    cout << "\n";
  }
  return 0;
}
