From 89ee25617b3410210e79a5078367a41e8c483a12 Mon Sep 17 00:00:00 2001
From: 0xff-dev <stevenshuang521@gmail.com>
Date: Thu, 26 Oct 2023 22:19:36 +0800
Subject: [PATCH] Add solution and test-cases for problem 823

---
 .../0823.Binary-Trees-With-Factors/README.md  | 27 ++++++++---------
 .../Solution.go                               | 30 +++++++++++++++++--
 .../Solution_test.go                          | 14 ++++-----
 3 files changed, 48 insertions(+), 23 deletions(-)

diff --git a/leetcode/801-900/0823.Binary-Trees-With-Factors/README.md b/leetcode/801-900/0823.Binary-Trees-With-Factors/README.md
index c4f599d8..14efe3ba 100644
--- a/leetcode/801-900/0823.Binary-Trees-With-Factors/README.md
+++ b/leetcode/801-900/0823.Binary-Trees-With-Factors/README.md
@@ -1,28 +1,27 @@
 # [823.Binary Trees With Factors][title]
 
-> [!WARNING|style:flat]
-> This question is temporarily unanswered if you have good ideas. Welcome to [Create Pull Request PR](https://github.com/kylesliu/awesome-golang-algorithm)
-
 ## Description
+Given an array of unique integers, `arr`, where each integer `arr[i]` 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 its children.
+
+Return the number of binary trees we can make. The answer may be too large so return the answer **modulo** `10^9 + 7`.
 
 **Example 1:**
 
 ```
-Input: a = "11", b = "1"
-Output: "100"
+Input: arr = [2,4]
+Output: 3
+Explanation: We can make these trees: [2], [4], [4, 2, 2]
 ```
 
-## 题意
-> ...
+**Example 2:**
 
-## 题解
-
-### 思路1
-> ...
-Binary Trees With Factors
-```go
 ```
-
+Input: arr = [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].
+```
 
 ## 结语
 
diff --git a/leetcode/801-900/0823.Binary-Trees-With-Factors/Solution.go b/leetcode/801-900/0823.Binary-Trees-With-Factors/Solution.go
index d115ccf5..c7e19f12 100644
--- a/leetcode/801-900/0823.Binary-Trees-With-Factors/Solution.go
+++ b/leetcode/801-900/0823.Binary-Trees-With-Factors/Solution.go
@@ -1,5 +1,31 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+import (
+	"sort"
+)
+
+const mod823 = 1000000007
+
+func Solution(arr []int) int {
+	ans := 0
+	set := make(map[uint64]int)
+	for _, n := range arr {
+		set[uint64(n)] = 1
+	}
+	sort.Ints(arr)
+	for i := 1; i < len(arr); i++ {
+		for j := i - 1; j >= 0; j-- {
+			if arr[i]%arr[j] == 0 {
+				tmp := uint64(arr[i]) / uint64(arr[j])
+				if count, ok := set[tmp]; ok {
+					a := set[uint64(arr[j])]
+					set[uint64(arr[i])] += (a * count) % mod823
+				}
+			}
+		}
+	}
+	for _, c := range set {
+		ans = (ans + c) % mod823
+	}
+	return ans
 }
diff --git a/leetcode/801-900/0823.Binary-Trees-With-Factors/Solution_test.go b/leetcode/801-900/0823.Binary-Trees-With-Factors/Solution_test.go
index 14ff50eb..f0243ad6 100644
--- a/leetcode/801-900/0823.Binary-Trees-With-Factors/Solution_test.go
+++ b/leetcode/801-900/0823.Binary-Trees-With-Factors/Solution_test.go
@@ -10,12 +10,12 @@ func TestSolution(t *testing.T) {
 	//	测试用例
 	cases := []struct {
 		name   string
-		inputs bool
-		expect bool
+		inputs []int
+		expect int
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase1", []int{2, 4}, 3},
+		{"TestCase2", []int{2, 4, 5, 10}, 7},
+		{"TestCase3", []int{2, 4, 5, 10, 100}, 17},
 	}
 
 	//	开始测试
@@ -30,10 +30,10 @@ func TestSolution(t *testing.T) {
 	}
 }
 
-//	压力测试
+// 压力测试
 func BenchmarkSolution(b *testing.B) {
 }
 
-//	使用案列
+// 使用案列
 func ExampleSolution() {
 }