diff --git a/cpp/2304/230409-CN.cpp b/cpp/2304/230409-CN.cpp
new file mode 100644
index 0000000..8dd8b49
--- /dev/null
+++ b/cpp/2304/230409-CN.cpp
@@ -0,0 +1,36 @@
+#include <string>
+#include <vector>
+#include <iostream>
+
+/**
+ * 2399. Check Distances Between Same Letters
+ *
+ * You are given a 0-indexed string s consisting of only lowercase English letters, where each letter in s appears exactly twice. You are also given a 0-indexed integer array distance of length 26.
+ * Each letter in the alphabet is numbered from 0 to 25 (i.e. 'a' -> 0, 'b' -> 1, 'c' -> 2, ... , 'z' -> 25).
+ * In a well-spaced string, the number of letters between the two occurrences of the ith letter is distance[i]. If the ith letter does not appear in s, then distance[i] can be ignored.
+ * Return true if s is a well-spaced string, otherwise return false.
+ */
+
+class Solution {
+public:
+	static bool checkDistances(const std::string&, const std::vector<int>&);
+};
+
+bool Solution::checkDistances(const std::string& s, const std::vector<int>& distance) {
+	int pos[26]{};
+	std::memset(pos, -1, sizeof pos);
+	for (int i = 0; i < s.length(); ++i) {
+		int& p = pos[s[i] - 'a'];
+		p = i + (p < 0 ? 1 : -p);
+	}
+	for (int i = 0; i < 26; ++i)
+		if (pos[i] >= 0 && pos[i] != distance[i])
+			return false;
+	return true;
+}
+
+int main() {
+	std::cout << Solution::checkDistances("abaccb", {
+		1,3,0,5,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
+	});
+}
diff --git a/cpp/2304/CMakeLists.txt b/cpp/2304/CMakeLists.txt
index 6f5347f..a1a839d 100644
--- a/cpp/2304/CMakeLists.txt
+++ b/cpp/2304/CMakeLists.txt
@@ -4,4 +4,4 @@ PROJECT(2304)
 SET(CMAKE_CXX_STANDARD 23)
 SET(CMAKE_EXPORT_COMPILE_COMMANDS true)
 
-ADD_EXECUTABLE(2304 230408.cpp)
+ADD_EXECUTABLE(2304 230409-CN.cpp)