#include <bits/stdc++.h>

using namespace std;

bool sorted(int a, int b, int c) {

    return (a < b and b < c) or (a > b and b > c);

}

void solve() {

    int n; cin >> n;

    int a[n] = {};

    for (int i = 0; i < n; i++)

        cin >> a[i];

    int len = n;

    bool skip[n] = {};

    for (int i = 1; i < n - 1; i++)

        if (sorted(a[i - 1], a[i], a[i + 1]))

            skip[i] = true, --len;

    cout << len << "\n";

    for (int i = 0; i < n; i++)

        if (!skip[i]) cout << a[i] << ' ';

    cout << "\n";

}

int main() {

    int t; cin >> t;

    while (t--) solve();

}