diff --git a/2201/220107-CN.cpp b/2201/220107-CN.cpp
new file mode 100644
index 0000000..776f9a3
--- /dev/null
+++ b/2201/220107-CN.cpp
@@ -0,0 +1,24 @@
+#include <cstdio>
+#include <string>
+
+class Solution {
+public:
+	static int maxDepth(const std::string& s) {
+		int ret = 0, current = 0;
+		for (const char* ptr = s.c_str(); *ptr; ++ptr)
+			switch (*ptr) {
+				case '(':
+					++current;
+					ret = current > ret ? current : ret;
+					break;
+				case ')':
+					--current;
+			}
+		return ret;
+	}
+};
+
+int main() {
+	std::printf("%d\n", Solution::maxDepth("()()()(()())"));
+	return 0;
+}