add: 230827

cpp/2308/CMakeLists.txt

@@ -0,0 +1,9 @@
+CMAKE_MINIMUM_REQUIRED(VERSION 3.24)
+PROJECT(2308)
+
+SET(CMAKE_CXX_STANDARD 23)
+SET(CMAKE_EXPORT_COMPILE_COMMANDS true)
+
+FILE(GLOB src *.cpp)
+
+ADD_EXECUTABLE(2308 ${src})

cpp/2308/LC230827.cpp

@@ -0,0 +1,40 @@
+#include <functional>
+#include <unordered_map>
+#include <vector>
+
+class LC230827 {
+public:
+	static bool canCross(const std::vector<int>&);
+};
+
+bool LC230827::canCross(const std::vector<int>& stones) {
+	if (stones[1] != 1)
+		return false;
+
+	const int n = stones.size();
+	std::unordered_map<unsigned long long, int> can_jump;
+	std::unordered_map<int, int> rev;
+	for (int i = 0; i < n; ++i)
+		rev[stones[i]] = i;
+
+	auto key_of = [&](int position, int k) {
+		return ((unsigned long long)(k) << 32) | position;
+	};
+
+	std::function<int(int, int)> dp = [&](int position, int k) {
+		if (position == n - 1)
+			return 1;
+		const auto key = key_of(position, k);
+		if (can_jump.count(key))
+			return can_jump[key];
+		int ret = 0;
+		for (int i = -1; i <= 1; ++i) {
+			if (k + i <= 0 || !rev.count(stones[position] + k + i))
+				continue;
+			ret |= dp(rev[stones[position] + k + i], k + i);
+		}
+		return can_jump[key] = ret;
+	};
+
+	return dp(1, 1);
+}

cpp/2308/data_structure.h

@@ -0,0 +1,28 @@
+#ifndef LEETCODE_CPP_DATA_STRUCTURE_H
+#define LEETCODE_CPP_DATA_STRUCTURE_H
+
+struct ListNode {
+	int val;
+	ListNode* next;
+
+	explicit ListNode(int x = 0, ListNode* next = nullptr) : val(x), next(next) {}
+};
+
+ListNode* construct(int x) {
+	return new ListNode(x);
+}
+
+template<typename... Ts>
+ListNode* construct(int x, Ts... xs) {
+	return new ListNode(x, construct(xs...));
+}
+
+struct TreeNode {
+	int val;
+	TreeNode* left;
+	TreeNode* right;
+
+	explicit TreeNode(int x, TreeNode* left = nullptr, TreeNode* right = nullptr) : val(x), left(left), right(right) {}
+};
+
+#endif //LEETCODE_CPP_DATA_STRUCTURE_H

cpp/2308/defs.h

@@ -0,0 +1,11 @@
+#ifndef LEETCODE_CPP_DEFS_H
+#define LEETCODE_CPP_DEFS_H
+
+#include <vector>
+
+class LC230827 {
+public:
+	static bool canCross(const std::vector<int>&);
+};
+
+#endif //LEETCODE_CPP_DEFS_H

cpp/2308/main.cpp

@@ -0,0 +1,8 @@
+#include "defs.h"
+#include <iostream>
+
+int main() {
+	LC230827 s;
+	std::cout << s.canCross({0,1,3,5,6,8,12,17});
+	return 0;
+}

cpp/CMakeLists.txt

@@ -31,5 +31,6 @@ ADD_EXECUTABLE(leetcode-cpp main.cpp 2302/230218.cpp 2302/230218-CN.cpp 2302/230
 # ADD_SUBDIRECTORY(2302)
 # ADD_SUBDIRECTORY(2303)
 # ADD_SUBDIRECTORY(2304)
-ADD_SUBDIRECTORY(2305)
+# ADD_SUBDIRECTORY(2305)
+ADD_SUBDIRECTORY(2308)
 ADD_SUBDIRECTORY(more)