diff --git a/cpp/2205/220528-CN.cpp b/cpp/2205/220528-CN.cpp
new file mode 100644
index 0000000..fe1ec95
--- /dev/null
+++ b/cpp/2205/220528-CN.cpp
@@ -0,0 +1,32 @@
+#include <string>
+#include <iostream>
+
+/**
+ * 1021. Remove Outermost Parentheses
+ * A valid parentheses string is either empty "", "(" + A + ")", or A + B, where A and B are valid parentheses strings, and + represents string concatenation.
+ * For example, "", "()", "(())()", and "(()(()))" are all valid parentheses strings.
+ * A valid parentheses string s is primitive if it is nonempty, and there does not exist a way to split it into s = A + B, with A and B nonempty valid parentheses strings.
+ * Given a valid parentheses string s, consider its primitive decomposition: s = P1 + P2 + ... + Pk, where Pi are primitive valid parentheses strings.
+ * Return s after removing the outermost parentheses of every primitive string in the primitive decomposition of s.
+ */
+
+class Solution {
+public:
+	static std::string removeOuterParentheses(const std::string& s) {
+		int stack = 0, prev = 0;
+		std::string ans;
+		const int n = s.length();
+		for (int i = 0; i < n; ++i) {
+			if (0 == (s[i] == '(' ? ++stack : --stack)) {
+				ans += s.substr(prev + 1, i - prev - 1);
+				prev = i + 1;
+			}
+		}
+		return ans;
+	}
+};
+
+int main() {
+	std::cout << Solution::removeOuterParentheses("()()");
+	return 0;
+}
diff --git a/cpp/2205/CMakeLists.txt b/cpp/2205/CMakeLists.txt
index b8cf7ea..d1b0f60 100644
--- a/cpp/2205/CMakeLists.txt
+++ b/cpp/2205/CMakeLists.txt
@@ -3,4 +3,4 @@ PROJECT(2205)
 
 SET(CMAKE_CXX_STANDARD 23)
 
-ADD_EXECUTABLE(2205 220528.cpp)
+ADD_EXECUTABLE(2205 220528-CN.cpp)