Translate all code to English (#1836)

* Review the EN heading format. * Fix pythontutor headings. * Fix pythontutor headings. * bug fixes * Fix headings in **/summary.md * Revisit the CN-to-EN translation for Python code using Claude-4.5 * Revisit the CN-to-EN translation for Java code using Claude-4.5 * Revisit the CN-to-EN translation for Cpp code using Claude-4.5. * Fix the dictionary. * Fix cpp code translation for the multipart strings. * Translate Go code to English. * Update workflows to test EN code. * Add EN translation for C. * Add EN translation for CSharp. * Add EN translation for Swift. * Trigger the CI check. * Revert. * Update en/hash_map.md * Add the EN version of Dart code. * Add the EN version of Kotlin code. * Add missing code files. * Add the EN version of JavaScript code. * Add the EN version of TypeScript code. * Fix the workflows. * Add the EN version of Ruby code. * Add the EN version of Rust code. * Update the CI check for the English version code. * Update Python CI check. * Fix cmakelists for en/C code. * Fix Ruby comments
2026-08-10 19:10:57 +00:00 · 2025-12-31 07:44:52 +08:00
parent 45e1295241
commit 2778a6f9c7
1284 changed files with 71557 additions and 3275 deletions
@@ -0,0 +1,49 @@
+/**
+* File: build_tree.cs
+* Created Time: 2023-07-18
+* Author: hpstory (hpstory1024@163.com)
+*/
+
+namespace hello_algo.chapter_divide_and_conquer;
+
+public class build_tree {
+    /* Build binary tree: divide and conquer */
+    TreeNode? DFS(int[] preorder, Dictionary<int, int> inorderMap, int i, int l, int r) {
+        // Terminate when the subtree interval is empty
+        if (r - l < 0)
+            return null;
+        // Initialize the root node
+        TreeNode root = new(preorder[i]);
+        // Query m to divide the left and right subtrees
+        int m = inorderMap[preorder[i]];
+        // Subproblem: build the left subtree
+        root.left = DFS(preorder, inorderMap, i + 1, l, m - 1);
+        // Subproblem: build the right subtree
+        root.right = DFS(preorder, inorderMap, i + 1 + m - l, m + 1, r);
+        // Return the root node
+        return root;
+    }
+
+    /* Build binary tree */
+    TreeNode? BuildTree(int[] preorder, int[] inorder) {
+        // Initialize hash map, storing the mapping from inorder elements to indices
+        Dictionary<int, int> inorderMap = [];
+        for (int i = 0; i < inorder.Length; i++) {
+            inorderMap.TryAdd(inorder[i], i);
+        }
+        TreeNode? root = DFS(preorder, inorderMap, 0, 0, inorder.Length - 1);
+        return root;
+    }
+
+    [Test]
+    public void Test() {
+        int[] preorder = [3, 9, 2, 1, 7];
+        int[] inorder = [9, 3, 1, 2, 7];
+        Console.WriteLine("Preorder traversal = " + string.Join(", ", preorder));
+        Console.WriteLine("Inorder traversal = " + string.Join(", ", inorder));
+
+        TreeNode? root = BuildTree(preorder, inorder);
+        Console.WriteLine("The constructed binary tree is:");
+        PrintUtil.PrintTree(root);
+    }
+}