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import { TreeNode } from "../binary-tree-inorder-traversal/TreeNode.ts";
export default function deepestLeavesSum(root: TreeNode | null): number {    if (!root) return 0;    let cur = [root];
    while (cur.length) {        const temp: typeof cur = [];
        cur.map((n) => [n.left, n.right].filter(Boolean)).forEach((a) =>            temp.push(...(a as TreeNode[]))        );
        if (!temp.length) {            return cur.reduce((a, v) => a + v.val, 0);        }        cur = temp;    }    return 0;}