0823-binary-trees-with-factors.adoc

823. Binary Trees With Factors

{leetcode}/problems/binary-trees-with-factors/[LeetCode - Binary Trees With Factors^]

Given an array of unique integers, each integer is strictly greater than 1.

We make a binary tree using these integers and each number may be used for any number of times.

Each non-leaf node’s value should be equal to the product of the values of it’s children.

How many binary trees can we make? Return the answer modulo 10 * 9 + 7*.

Example 1:

Input: A = [2, 4]
Output: 3
Explanation: We can make these trees: [2], [4], [4, 2, 2]

Example 2:

Input: A = [2, 4, 5, 10]
Output: 7
Explanation: We can make these trees: [2], [4], [5], [10], [4, 2, 2], [10, 2, 5], [10, 5, 2].

Note:

1. 1 ⇐ A.length ⇐ 1000.

2. 2 ⇐ A[i] ⇐ 10 ^ 9.

link:{sourcedir}/_0823_BinaryTreesWithFactors.java[role=include]