From 54144f3a6b59bb8be22111a489d60edc49eeffa9 Mon Sep 17 00:00:00 2001
From: Relsola <sola001018@gmail.com>
Date: Fri, 27 Oct 2023 19:49:03 +0800
Subject: [PATCH] =?UTF-8?q?Update=2098.=E9=AA=8C=E8=AF=81=E4=BA=8C?=
 =?UTF-8?q?=E5=8F=89=E6=90=9C=E7=B4=A2=E6=A0=91.md=20=E5=A2=9E=E5=8A=A0js?=
 =?UTF-8?q?=E5=92=8Cts=E8=BF=AD=E4=BB=A3=E8=A7=A3=E6=B3=95?=
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---
 problems/0098.验证二叉搜索树.md | 61 ++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)

diff --git a/problems/0098.验证二叉搜索树.md b/problems/0098.验证二叉搜索树.md
index 0a64266e..184060a5 100644
--- a/problems/0098.验证二叉搜索树.md
+++ b/problems/0098.验证二叉搜索树.md
@@ -595,6 +595,43 @@ var isValidBST = function (root) {
 };
 ```
 
+> 迭代法:
+
+```JavaScript
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {TreeNode} root
+ * @return {boolean}
+ */
+let pre = null;
+var isValidBST = function (root) {
+	const queue = [];
+	let cur = root;
+	let pre = null;
+	while (cur !== null || queue.length !== 0) {
+		if (cur !== null) {
+			queue.push(cur);
+			cur = cur.left;
+		} else {
+			cur = queue.pop();
+			if (pre !== null && cur.val <= pre.val) {
+				return false;
+			}
+			pre = cur;
+			cur = cur.right;
+		}
+	}
+	return true;
+};
+```
+
 ### TypeScript
 
 > 辅助数组解决：
@@ -637,6 +674,30 @@ function isValidBST(root: TreeNode | null): boolean {
 };
 ```
 
+> 迭代法:
+
+```TypeScript
+function isValidBST(root: TreeNode | null): boolean {
+	const queue: TreeNode[] = [];
+	let cur: TreeNode | null = root;
+	let pre: TreeNode | null = null;
+	while (cur !== null || queue.length !== 0) {
+		if (cur !== null) {
+			queue.push(cur);
+			cur = cur.left;
+		} else {
+			cur = queue.pop()!;
+			if (pre !== null && cur!.val <= pre.val) {
+				return false;
+			}
+			pre = cur;
+			cur = cur!.right;
+		}
+	}
+	return true;
+}
+```
+
 ### Scala
 
 辅助数组解决: