C - LIS or Reverse LIS?

https://codeforces.com/contest/1682/submission/158040482

Codeforces/1682/C/C.cpp

@@ -0,0 +1,42 @@
+#include <algorithm>
+#include <cmath>
+#include <iostream>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+const int N = 2e5 + 5;
+
+int t, n, a[N];
+
+int main() {
+    std::ios::sync_with_stdio(false);
+
+    cin >> t;
+
+    while (t--) {
+        int ans = 2;
+
+        cin >> n;
+
+        for (int i = 1; i <= n; i++) {
+            cin >> a[i];
+        }
+
+        if (n <= 2) {
+            cout << 1 << endl;
+            continue;
+        }
+
+        std::sort(a + 1, a + 1 + n);
+
+        for (int i = 3; i <= n; i++) {
+            if (a[i] != a[i - 2]) ans++;
+        }
+
+        cout << (ans + 1) / 2 << endl;
+    }
+
+    return 0;
+}