add: 230414

cpp/2304/230414.cpp

@@ -0,0 +1,46 @@
+#include <algorithm>
+#include <string>
+#include <iostream>
+
+/**
+ * 516. Longest Palindromic Subsequence
+ *
+ * Given a string s, find the longest palindromic subsequence's length in s.
+ * A subsequence is a sequence that can be derived from another sequence by deleting some or no elements without changing the order of the remaining elements.
+ */
+
+class Solution {
+private:
+	std::string s;
+	int ans[1001][1001]{};
+
+	int dp(int, int);
+
+public:
+	int longestPalindromeSubseq(std::string);
+};
+
+int Solution::longestPalindromeSubseq(std::string str) {
+	this->s = std::move(str);
+	return dp(0, s.size() - 1);
+}
+
+int Solution::dp(int x, int y) {
+	int& a = ans[x][y];
+	if (a)
+		return a;
+	if (x == y)
+		return a = 1;
+	if (1 == y - x)
+		return a = 1 + (s[x] == s[y]);
+	return a = std::max(
+		(s[x] == s[y]) * 2 + dp(x + 1, y - 1),
+		std::max(dp(x + 1, y), dp(x, y - 1))
+	);
+}
+
+int main() {
+	auto* s = new Solution;
+	std::cout << s->longestPalindromeSubseq("cbbd");
+	return 0;
+}

cpp/2304/CMakeLists.txt

@@ -4,4 +4,4 @@ PROJECT(2304)
 SET(CMAKE_CXX_STANDARD 23)
 SET(CMAKE_EXPORT_COMPILE_COMMANDS true)
 
-ADD_EXECUTABLE(2304 230414-CN.cpp)
+ADD_EXECUTABLE(2304 230414.cpp)