From cc55911d89f7b4f292e9673577cbd5faeba296e1 Mon Sep 17 00:00:00 2001
From: Lam Haoyin <root@eatswap.org>
Date: Thu, 6 Jan 2022 00:16:25 +0800
Subject: [PATCH] add: 220105 [Not a good example!]

---
 2201/220105.cpp     | 135 ++++++++++++++++++++++++++++++++++++++++++++
 2201/CMakeLists.txt |   2 +-
 2 files changed, 136 insertions(+), 1 deletion(-)
 create mode 100644 2201/220105.cpp

diff --git a/2201/220105.cpp b/2201/220105.cpp
new file mode 100644
index 0000000..ceb652d
--- /dev/null
+++ b/2201/220105.cpp
@@ -0,0 +1,135 @@
+#include <vector>
+#include <string>
+#include <set>
+#include <chrono>
+#include <iostream>
+
+/**
+ * 131. Palindrome Partitioning
+ * Given a string s, partition s such that every substring of the partition is a palindrome. Return all possible palindrome partitioning of s.
+ *
+ * A palindrome string is a string that reads the same backward as forward.
+ */
+
+class Solution {
+private:
+	// isPalindromeS[L][R] -> 0: not visited, 1: is, -1: is not a palindrome.
+	int isPalindromeS[17][17]{};
+	int hasPalindromeS[17][17]{};
+	int sameTo[17]{};
+	int strLen = -1;
+	const char* str = nullptr;
+
+	/**
+	 * whether str[L..R], ranged [L, R], is a palindrome.
+	 * @param L Index of the left of the range, included.
+	 * @param R ditto
+	 * @return -1 -> is not, 1 -> is palindrome.
+	 */
+	int isPalindrome(int L, int R) {
+		if (L > R) return -1;
+		if (isPalindromeS[L][R]) return isPalindromeS[L][R];
+		switch (R - L) {
+			case 0:
+				return isPalindromeS[L][R] = 1;
+			case 1:
+				return isPalindromeS[L][R] = (str[L] == str[R] ? 1 : -1);
+			default:
+				return isPalindromeS[L][R] = (str[L] == str[R] ? isPalindrome(L + 1, R - 1) : -1);
+		}
+	}
+
+	int hasPalindrome(int L, int R) {
+		if (hasPalindromeS[L][R]) return hasPalindromeS[L][R];
+		if (L >= R) return hasPalindromeS[L][R] = -1;
+		if (isPalindrome(L, R)) return 1;
+		switch (R - L) {
+			case 1:
+				return hasPalindromeS[L][R] = isPalindrome(L, R);
+			default:
+				return hasPalindromeS[L][R] = (hasPalindrome(L + 1, R) == 1 || hasPalindrome(L, R - 1) == 1 ? 1 : -1);
+		}
+	}
+
+	std::vector<std::vector<std::string>> generate(int cnt, char ch, std::vector<std::vector<std::string>>* const dpp) {
+		if (dpp[cnt].size()) return dpp[cnt];
+		if (cnt == 1) {
+			return dpp[1] = {{std::string(1, ch)}};
+		}
+		std::vector<std::vector<std::string>> ret;
+		for (int i = 1; i < cnt; ++i) {
+			auto th = generate(cnt - i, ch, dpp);
+			for (auto& j : th) {
+				j.insert(j.begin(), std::string(i, ch));
+			}
+			ret.insert(ret.end(), th.begin(), th.end());
+		}
+		ret.push_back({std::string(cnt, ch)});
+		return dpp[cnt] = ret;
+	}
+
+	// Partition of [L, R]
+	std::vector<std::vector<std::string>> getPartition(int L, int R) {
+		// Partition of [L, i], [i + 1, R]
+		std::vector<std::vector<std::string>> ret;
+		if (sameTo[L] == sameTo[R]) {
+			int cnt = R - L + 1;
+			std::vector<std::vector<std::string>> dpp[cnt+3];
+			return generate(cnt, str[L], dpp);
+		}
+		if (hasPalindrome(L, R) != 1) {
+			ret = {{}};
+			auto& t = ret[0];
+			for (int i = L; i <= R; ++i) {
+				t.emplace_back(str + i, 1);
+			}
+			return ret;
+		}
+		if (isPalindrome(L, R) == 1) {
+			ret.push_back({std::string(str + L, R - L + 1)});
+		}
+		for (int i = L; i < R; ++i) {
+			auto left = getPartition(L, i);
+			auto right = getPartition(i + 1, R);
+			for (const auto& j: left) {
+				for (const auto& k: right) {
+					ret.push_back(j);
+					auto& thisVec = ret.back();
+					thisVec.insert(thisVec.end(), k.begin(), k.end());
+				}
+			}
+		}
+		std::set<std::vector<std::string>> s;
+		s.insert(ret.begin(), ret.end());
+		return {s.begin(), s.end()};
+	}
+
+public:
+	// Partition of [L, R) is all Cartesian Product of [L, M) and [M, R)'s partition.
+	std::vector<std::vector<std::string>> partition(const std::string& s) {
+		this->strLen = s.length();
+		this->str = s.c_str();
+		auto t2 = std::chrono::high_resolution_clock::now();
+
+		for (int i = 1; i < this->strLen; ++i) {
+			if (str[i] == str[i - 1]) {
+				sameTo[i] = sameTo[i - 1];
+			} else {
+				sameTo[i] = i;
+			}
+		}
+
+		auto ret = this->getPartition(0, this->strLen - 1);
+
+		auto t3 = std::chrono::high_resolution_clock::now();
+		std::cout << std::chrono::duration_cast<std::chrono::milliseconds>(t3 - t2).count() << "ms" << std::endl;
+		return ret;
+	}
+};
+
+int main() {
+	Solution solver;
+	auto ans = solver.partition("aaaaaaaaaaaaaaaa");
+	std::cout << ans.size();
+	return 0;
+}
\ No newline at end of file
diff --git a/2201/CMakeLists.txt b/2201/CMakeLists.txt
index faf7f39..daff41d 100644
--- a/2201/CMakeLists.txt
+++ b/2201/CMakeLists.txt
@@ -3,4 +3,4 @@ PROJECT(2201)
 
 SET(CMAKE_CXX_STANDARD 23)
 
-ADD_EXECUTABLE(2201 220105-CN.cpp)
\ No newline at end of file
+ADD_EXECUTABLE(2201 220105.cpp)
\ No newline at end of file