add: 230316

cpp/2303/230316.cpp

@@ -0,0 +1,42 @@
+#include <vector>
+
+struct TreeNode {
+	int val;
+	TreeNode* left;
+	TreeNode* right;
+
+	explicit TreeNode(int x, TreeNode* left = nullptr, TreeNode* right = nullptr) : val(x), left(left), right(right) {}
+};
+
+/**
+ * 106. Construct Binary Tree from Inorder and Postorder Traversal
+ *
+ * Given two integer arrays inorder and postorder where inorder is the inorder traversal of a binary tree and postorder is the postorder traversal of the same tree, construct and return the binary tree.
+ */
+
+using VCI = std::vector<int>::const_iterator;
+
+class Solution {
+private:
+	static TreeNode* bT(VCI is, VCI ie, VCI ps, VCI pe) {
+		if (is == ie || ps == pe)
+			return nullptr;
+		int r = *(pe - 1);
+		int pos = std::find(is, ie, r) - is;
+		return new TreeNode(
+			r,
+			bT(is, is + pos, ps, ps + pos),
+			bT(is + pos + 1, ie, ps + pos, pe - 1)
+		);
+	}
+
+public:
+	static TreeNode* buildTree(const std::vector<int>& inorder, const std::vector<int>& postorder) {
+		return bT(inorder.begin(), inorder.end(), postorder.begin(), postorder.end());
+	}
+};
+
+int main() {
+	Solution::buildTree({-1}, {-1});
+	return 0;
+}

cpp/2303/CMakeLists.txt

@@ -3,4 +3,4 @@ PROJECT(2303)
 
 SET(CMAKE_CXX_STANDARD 23)
 
-ADD_EXECUTABLE(2303 230316-CN.cpp)
+ADD_EXECUTABLE(2303 230316.cpp)