添加(0098.验证二叉搜索树.md):增加typescript版本

This commit is contained in:
Steve2020
2022-02-17 15:07:13 +08:00
parent 1dad8a6003
commit 7af58b92b8

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@ -526,6 +526,48 @@ var isValidBST = function (root) {
};
```
## TypeScript
> 辅助数组解决:
```typescript
function isValidBST(root: TreeNode | null): boolean {
const traversalArr: number[] = [];
function inorderTraverse(root: TreeNode | null): void {
if (root === null) return;
inorderTraverse(root.left);
traversalArr.push(root.val);
inorderTraverse(root.right);
}
inorderTraverse(root);
for (let i = 0, length = traversalArr.length; i < length - 1; i++) {
if (traversalArr[i] >= traversalArr[i + 1]) return false;
}
return true;
};
```
> 递归中解决:
```typescript
function isValidBST(root: TreeNode | null): boolean {
let maxVal = -Infinity;
function inorderTraverse(root: TreeNode | null): boolean {
if (root === null) return true;
let leftValid: boolean = inorderTraverse(root.left);
if (!leftValid) return false;
if (maxVal < root.val) {
maxVal = root.val
} else {
return false;
}
let rightValid: boolean = inorderTraverse(root.right);
return leftValid && rightValid;
}
return inorderTraverse(root);
};
```
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