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
2026-09-20 21:36:33 +08:00 · 2025-12-31 07:44:52 +08:00
parent 45e1295241
commit 2778a6f9c7
1284 changed files with 71557 additions and 3275 deletions
@@ -0,0 +1,230 @@
+/**
+ * File: avl_tree.swift
+ * Created Time: 2023-01-28
+ * Author: nuomi1 (nuomi1@qq.com)
+ */
+
+import utils
+
+/* AVL tree */
+class AVLTree {
+    fileprivate var root: TreeNode? // Root node
+
+    init() {}
+
+    /* Get node height */
+    func height(node: TreeNode?) -> Int {
+        // Empty node height is -1, leaf node height is 0
+        node?.height ?? -1
+    }
+
+    /* Update node height */
+    private func updateHeight(node: TreeNode?) {
+        // Node height equals the height of the tallest subtree + 1
+        node?.height = max(height(node: node?.left), height(node: node?.right)) + 1
+    }
+
+    /* Get balance factor */
+    func balanceFactor(node: TreeNode?) -> Int {
+        // Empty node balance factor is 0
+        guard let node = node else { return 0 }
+        // Node balance factor = left subtree height - right subtree height
+        return height(node: node.left) - height(node: node.right)
+    }
+
+    /* Right rotation operation */
+    private func rightRotate(node: TreeNode?) -> TreeNode? {
+        let child = node?.left
+        let grandChild = child?.right
+        // Using child as pivot, rotate node to the right
+        child?.right = node
+        node?.left = grandChild
+        // Update node height
+        updateHeight(node: node)
+        updateHeight(node: child)
+        // Return root node of subtree after rotation
+        return child
+    }
+
+    /* Left rotation operation */
+    private func leftRotate(node: TreeNode?) -> TreeNode? {
+        let child = node?.right
+        let grandChild = child?.left
+        // Using child as pivot, rotate node to the left
+        child?.left = node
+        node?.right = grandChild
+        // Update node height
+        updateHeight(node: node)
+        updateHeight(node: child)
+        // Return root node of subtree after rotation
+        return child
+    }
+
+    /* Perform rotation operation to restore balance to this subtree */
+    private func rotate(node: TreeNode?) -> TreeNode? {
+        // Get balance factor of node
+        let balanceFactor = balanceFactor(node: node)
+        // Left-leaning tree
+        if balanceFactor > 1 {
+            if self.balanceFactor(node: node?.left) >= 0 {
+                // Right rotation
+                return rightRotate(node: node)
+            } else {
+                // First left rotation then right rotation
+                node?.left = leftRotate(node: node?.left)
+                return rightRotate(node: node)
+            }
+        }
+        // Right-leaning tree
+        if balanceFactor < -1 {
+            if self.balanceFactor(node: node?.right) <= 0 {
+                // Left rotation
+                return leftRotate(node: node)
+            } else {
+                // First right rotation then left rotation
+                node?.right = rightRotate(node: node?.right)
+                return leftRotate(node: node)
+            }
+        }
+        // Balanced tree, no rotation needed, return directly
+        return node
+    }
+
+    /* Insert node */
+    func insert(val: Int) {
+        root = insertHelper(node: root, val: val)
+    }
+
+    /* Recursively insert node (helper method) */
+    private func insertHelper(node: TreeNode?, val: Int) -> TreeNode? {
+        var node = node
+        if node == nil {
+            return TreeNode(x: val)
+        }
+        /* 1. Find insertion position and insert node */
+        if val < node!.val {
+            node?.left = insertHelper(node: node?.left, val: val)
+        } else if val > node!.val {
+            node?.right = insertHelper(node: node?.right, val: val)
+        } else {
+            return node // Duplicate node not inserted, return directly
+        }
+        updateHeight(node: node) // Update node height
+        /* 2. Perform rotation operation to restore balance to this subtree */
+        node = rotate(node: node)
+        // Return root node of subtree
+        return node
+    }
+
+    /* Remove node */
+    func remove(val: Int) {
+        root = removeHelper(node: root, val: val)
+    }
+
+    /* Recursively delete node (helper method) */
+    private func removeHelper(node: TreeNode?, val: Int) -> TreeNode? {
+        var node = node
+        if node == nil {
+            return nil
+        }
+        /* 1. Find node and delete */
+        if val < node!.val {
+            node?.left = removeHelper(node: node?.left, val: val)
+        } else if val > node!.val {
+            node?.right = removeHelper(node: node?.right, val: val)
+        } else {
+            if node?.left == nil || node?.right == nil {
+                let child = node?.left ?? node?.right
+                // Number of child nodes = 0, delete node directly and return
+                if child == nil {
+                    return nil
+                }
+                // Number of child nodes = 1, delete node directly
+                else {
+                    node = child
+                }
+            } else {
+                // Number of child nodes = 2, delete the next node in inorder traversal and replace current node with it
+                var temp = node?.right
+                while temp?.left != nil {
+                    temp = temp?.left
+                }
+                node?.right = removeHelper(node: node?.right, val: temp!.val)
+                node?.val = temp!.val
+            }
+        }
+        updateHeight(node: node) // Update node height
+        /* 2. Perform rotation operation to restore balance to this subtree */
+        node = rotate(node: node)
+        // Return root node of subtree
+        return node
+    }
+
+    /* Search node */
+    func search(val: Int) -> TreeNode? {
+        var cur = root
+        while cur != nil {
+            // Target node is in cur's right subtree
+            if cur!.val < val {
+                cur = cur?.right
+            }
+            // Target node is in cur's left subtree
+            else if cur!.val > val {
+                cur = cur?.left
+            }
+            // Found target node, exit loop
+            else {
+                break
+            }
+        }
+        // Return target node
+        return cur
+    }
+}
+
+@main
+enum _AVLTree {
+    static func testInsert(tree: AVLTree, val: Int) {
+        tree.insert(val: val)
+        print("\nAfter inserting node \(val), AVL tree is")
+        PrintUtil.printTree(root: tree.root)
+    }
+
+    static func testRemove(tree: AVLTree, val: Int) {
+        tree.remove(val: val)
+        print("\nAfter deleting node \(val), AVL tree is")
+        PrintUtil.printTree(root: tree.root)
+    }
+
+    /* Driver Code */
+    static func main() {
+        /* Please pay attention to how the AVL tree maintains balance after inserting nodes */
+        let avlTree = AVLTree()
+
+        /* Insert node */
+        // Delete nodes
+        testInsert(tree: avlTree, val: 1)
+        testInsert(tree: avlTree, val: 2)
+        testInsert(tree: avlTree, val: 3)
+        testInsert(tree: avlTree, val: 4)
+        testInsert(tree: avlTree, val: 5)
+        testInsert(tree: avlTree, val: 8)
+        testInsert(tree: avlTree, val: 7)
+        testInsert(tree: avlTree, val: 9)
+        testInsert(tree: avlTree, val: 10)
+        testInsert(tree: avlTree, val: 6)
+
+        /* Please pay attention to how the AVL tree maintains balance after deleting nodes */
+        testInsert(tree: avlTree, val: 7)
+
+        /* Remove node */
+        // Delete node with degree 1
+        testRemove(tree: avlTree, val: 8) // Delete node with degree 2
+        testRemove(tree: avlTree, val: 5) // Remove node with degree 1
+        testRemove(tree: avlTree, val: 4) // Remove node with degree 2
+
+        /* Search node */
+        let node = avlTree.search(val: 7)
+        print("\nFound node object is \(node!), node value = \(node!.val)")
+    }
+}