diff --git a/2201/220125-CN.cpp b/2201/220125-CN.cpp
index 4df90fa..e51cb48 100644
--- a/2201/220125-CN.cpp
+++ b/2201/220125-CN.cpp
@@ -21,6 +21,14 @@ public:
 	}
 };
 
+/**
+ * 1688. Count of Matches in Tournament
+ * You are given an integer n, the number of teams in a tournament that has strange rules:
+ * If the current number of teams is even, each team gets paired with another team. A total of n / 2 matches are played, and n / 2 teams advance to the next round.
+ * If the current number of teams is odd, one team randomly advances in the tournament, and the rest gets paired. A total of (n - 1) / 2 matches are played, and (n - 1) / 2 + 1 teams advance to the next round.
+ * Return the number of matches played in the tournament until a winner is decided.
+ */
+
 class Solution {
 public:
 	inline static constexpr int numberOfMatches(int n) {
diff --git a/2201/220125.cpp b/2201/220125.cpp
new file mode 100644
index 0000000..f9abf72
--- /dev/null
+++ b/2201/220125.cpp
@@ -0,0 +1,25 @@
+#include <vector>
+#include <algorithm>
+#include <cstdio>
+
+/**
+ * 941. Valid Mountain Array
+ * Given an array of integers arr, return true if and only if it is a valid mountain array.
+ * Recall that arr is a mountain array if and only if:
+ *  - arr.length >= 3
+ *  - There exists some i with 0 < i < arr.length - 1 such that:
+ *    - arr[0] < arr[1] < ... < arr[i - 1] < arr[i]
+ *    - arr[i] > arr[i + 1] > ... > arr[arr.length - 1]
+ */
+
+class Solution {
+public:
+	static bool validMountainArray(const std::vector<int>& arr) {
+		return std::max_element(arr.begin(), arr.end()) != arr.end() - 1 && std::max_element(arr.begin(), arr.end()) != arr.begin() && std::adjacent_find(arr.begin(), std::max_element(arr.begin(), arr.end()), std::greater_equal<>()) == std::max_element(arr.begin(), arr.end()) && std::adjacent_find(std::max_element(arr.begin(), arr.end()), arr.end(), std::less_equal<>()) == arr.end();
+	}
+};
+
+int main() {
+	std::printf("%s\n", Solution::validMountainArray({0, 3, 2, 1}) ? "true" : "false");
+	return 0;
+}
diff --git a/2201/CMakeLists.txt b/2201/CMakeLists.txt
index cacd355..54f87c2 100644
--- a/2201/CMakeLists.txt
+++ b/2201/CMakeLists.txt
@@ -3,4 +3,4 @@ PROJECT(2201)
 
 SET(CMAKE_CXX_STANDARD 23)
 
-ADD_EXECUTABLE(2201 220125-CN.cpp)
+ADD_EXECUTABLE(2201 220125.cpp)