diff --git a/cpp/2304/230404.cpp b/cpp/2304/230404.cpp
new file mode 100644
index 0000000..0615da3
--- /dev/null
+++ b/cpp/2304/230404.cpp
@@ -0,0 +1,29 @@
+#include <string>
+#include <iostream>
+
+/**
+ * 2405. Optimal Partition of String
+ *
+ * Given a string s, partition the string into one or more substrings such that the characters in each substring are unique. That is, no letter appears in a single substring more than once.
+ * Return the minimum number of substrings in such a partition.
+ * Note that each character should belong to exactly one substring in a partition.
+ */
+
+class Solution {
+public:
+	static int partitionString(const std::string& s) {
+		int set = 0, ans = 0;
+		for (auto&& ch : s) {
+			if (int c = 1 << (ch - 'a'); set & c) {
+				set = c;
+				++ans;
+			} else set |= c;
+		}
+		return ans + !!set;
+	}
+};
+
+int main() {
+	std::cout << Solution::partitionString("abacaba");
+	return 0;
+}
diff --git a/cpp/2304/CMakeLists.txt b/cpp/2304/CMakeLists.txt
index 56933e0..e14ecf6 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 230404-CN.cpp)
+ADD_EXECUTABLE(2304 230404.cpp)