diff --git a/problems/0450.删除二叉搜索树中的节点.md b/problems/0450.删除二叉搜索树中的节点.md index 2e333530..cc29bea4 100644 --- a/problems/0450.删除二叉搜索树中的节点.md +++ b/problems/0450.删除二叉搜索树中的节点.md @@ -518,6 +518,70 @@ var deleteNode = function (root, key) { } ``` +## TypeScript + +> 递归法: + +```typescript +function deleteNode(root: TreeNode | null, key: number): TreeNode | null { + if (root === null) return null; + if (root.val === key) { + if (root.left === null && root.right === null) return null; + if (root.left === null) return root.right; + if (root.right === null) return root.left; + let curNode: TreeNode = root.right; + while (curNode.left !== null) { + curNode = curNode.left; + } + curNode.left = root.left; + return root.right; + } + if (root.val > key) root.left = deleteNode(root.left, key); + if (root.val < key) root.right = deleteNode(root.right, key); + return root; +}; +``` + +> 迭代法: + +```typescript +function deleteNode(root: TreeNode | null, key: number): TreeNode | null { + function removeTargetNode(root: TreeNode): TreeNode | null { + if (root.left === null && root.right === null) return null; + if (root.right === null) return root.left; + if (root.left === null) return root.right; + let curNode: TreeNode | null = root.right; + while (curNode.left !== null) { + curNode = curNode.left; + } + curNode.left = root.left; + return root.right; + } + let preNode: TreeNode | null = null, + curNode: TreeNode | null = root; + while (curNode !== null) { + if (curNode.val === key) break; + preNode = curNode; + if (curNode.val > key) { + curNode = curNode.left; + } else { + curNode = curNode.right; + } + } + if (curNode === null) return root; + if (preNode === null) { + // 删除头节点 + return removeTargetNode(curNode); + } + if (preNode.val > key) { + preNode.left = removeTargetNode(curNode); + } else { + preNode.right = removeTargetNode(curNode); + } + return root; +}; +``` + -----------------------