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import { TreeNode } from "../binary-tree-inorder-traversal/TreeNode.ts";
class BSTIterator {    #root: TreeNode | null | undefined;    #stack: TreeNode[] = [];    #cur: TreeNode | null | undefined;    constructor(root: TreeNode | null) {        this.#root = root;        this.#cur = root;    }
    next(): number {        if (!this.#root) {            return -Infinity;        }        while (this.#cur) {            this.#stack.push(this.#cur);            this.#cur = this.#cur.left;        }        const cur = this.#stack.pop();        const ret = cur?.val;        this.#cur = cur?.right;
        return ret ?? Infinity;    }
    hasNext(): boolean {        if (!this.#root) {            return false;        }        return !!(this.#stack.length || this.#cur);    }}
export default BSTIterator;