diff --git a/cpp/2308/LC231014.cpp b/cpp/2308/LC231014.cpp
new file mode 100644
index 0000000..73bc65a
--- /dev/null
+++ b/cpp/2308/LC231014.cpp
@@ -0,0 +1,23 @@
+#include "defs.h"
+#include <algorithm>
+#include <functional>
+#include <unordered_map>
+
+int LC231014::paintWalls(const std::vector<int>& cost, const std::vector<int>& time) {
+	int n = cost.size();
+
+	std::unordered_map<int, int> ans;
+	std::function<int(int, int)> dp = [&](int pos, int rem_free) {
+		if (pos + rem_free >= n)
+			return 0;
+		if (pos == n - 1)
+			return (rem_free + time[pos] < 0) ? 0x70000000 : cost[pos];
+		// rem_free < (1 << 21)
+		int& ret = ans[((rem_free + 505 * 505) << 10) | pos];
+		return ret ? ret : ret = std::min(dp(pos + 1, rem_free + time[pos]) + cost[pos], dp(pos + 1, rem_free - 1));
+	};
+
+	return dp(0, 0);
+}
+
+using Solution = LC231014;
diff --git a/cpp/2308/defs.h b/cpp/2308/defs.h
index 42b50a7..fa640a8 100644
--- a/cpp/2308/defs.h
+++ b/cpp/2308/defs.h
@@ -31,4 +31,9 @@ public:
 	static std::string decodeAtIndex(const std::string& s, int k);
 };
 
+class LC231014 {
+public:
+	static int paintWalls(const std::vector<int>&, const std::vector<int>&);
+};
+
 #endif //LEETCODE_CPP_DEFS_H