feat: azl397985856#172 azl397985856#263 azl397985856#342 azl397985856#575

Author: luzhipeng

172.factorial-trailing-zeroes.js

@@ -97,10 +97,11 @@ The data structures mainly includes:
 - [0020.Valid Parentheses](./problems/20.validParentheses.md)
 - [0026.remove-duplicates-from-sorted-array](./problems/26.remove-duplicates-from-sorted-array.md)
 - [0088.merge-sorted-array](./problems/88.merge-sorted-array.md)
-- [0121.best-time-to-buy-and-sell-stock](./problems/121.best-time-to-buy-and-sell-stock.md) 🆕
-- [0122.best-time-to-buy-and-sell-stock-ii](./problems/122.best-time-to-buy-and-sell-stock-ii.md) 🆕
+- [0121.best-time-to-buy-and-sell-stock](./problems/121.best-time-to-buy-and-sell-stock.md)
+- [0122.best-time-to-buy-and-sell-stock-ii](./problems/122.best-time-to-buy-and-sell-stock-ii.md)
 - [0136.single-number](./problems/136.single-number.md)
 - [0167.two-sum-ii-input-array-is-sorted](./problems/167.two-sum-ii-input-array-is-sorted.md)
+- [0172.factorial-trailing-zeroes](./problems/172.factorial-trailing-zeroes.md) 🆕
 - [0169.majority-element](./problems/169.majority-element.md)
 - [0190.reverse-bits](./problems/190.reverse-bits.md)
 - [0191.number-of-1-bits](./problems/191.number-of-1-bits.md)
@@ -109,24 +110,27 @@ The data structures mainly includes:
 - [0206.reverse-linked-list](./problems/206.reverse-linked-list.md)
 - [0219.contains-duplicate-ii](./problems/219.contains-duplicate-ii.md)
 - [0226.invert-binary-tree](./problems/226.invert-binary-tree.md)
+- [0263.ugly-number](./problems/263.ugly-number.md) 🆕
 - [0283.move-zeroes](./problems/283.move-zeroes.md)
+- [0342.power-of-four](./problems/342.power-of-four.md) 🆕
 - [0349.intersection-of-two-arrays](./problems/349.intersection-of-two-arrays.md)
+- [0575.distribute-candies](./problems/575.distribute-candies.md) 🆕
 
 
 #### Medium
 
 - [0002. Add Two Numbers](./problems/2.addTwoNumbers.md)
 - [0003. Longest Substring Without Repeating Characters](./problems/3.longestSubstringWithoutRepeatingCharacters.md)
 - [0011.container-with-most-water](./problems/11.container-with-most-water.md)
-- [0015.3-sum](./problems/15.3-sum.md) 🆕
+- [0015.3-sum](./problems/15.3-sum.md)
 - [0019. Remove Nth Node From End of List](./problems/19.removeNthNodeFromEndofList.md)
 - [0024. Swap Nodes In Pairs](./problems/24.swapNodesInPairs.md)
 - [0039.combination-sum](./problems/39.combination-sum.md)
 - [0040.combination-sum-ii](./problems/40.combination-sum-ii.md)
 - [0046.permutations](./problems/46.permutations.md)
 - [0047.permutations-ii](./problems/47.permutations-ii.md)
-- [0055.jump-game](./problems/55.jump-game.md) 🆕 
-- [0062.unique-paths](./problems/62.unique-paths.md )🆕 
+- [0055.jump-game](./problems/55.jump-game.md)
+- [0062.unique-paths](./problems/62.unique-paths.md )
 - [0075.sort-colors](./problems/75.sort-colors.md)
 - [0078.subsets](./problems/78.subsets.md) 
 - [0086.partition-list](./problems/86.partition-list.md)
@@ -138,12 +142,12 @@ The data structures mainly includes:
 - [0103.binary-tree-zigzag-level-order-traversal](./problems/103.binary-tree-zigzag-level-order-traversal.md)
 - [0139.word-break](./problems/139.word-breakmd)
 - [0144.binary-tree-preorder-traversal](./problems/144.binary-tree-preorder-traversal.md)
-- [0150.evaluate-reverse-polish-notation](./problems/150.evaluate-reverse-polish-notation.md) 🖊
+- [0150.evaluate-reverse-polish-notation](./problems/150.evaluate-reverse-polish-notation.md)
 - [0152.maximum-product-subarray](./problems/152.maximum-product-subarray.md) 🆕  
 - [0199.binary-tree-right-side-view](./problems/199.binary-tree-right-side-view.md)
 - [0201.bitwise-and-of-numbers-range](./problems/201.bitwise-and-of-numbers-range.md)
 - [0208.implement-trie-prefix-tree](./problems/208.implement-trie-prefix-tree.md)
-- [0209.minimum-size-subarray-sum](./problems/209.minimum-size-subarray-sum.md) 🖊 
+- [0209.minimum-size-subarray-sum](./problems/209.minimum-size-subarray-sum.md)
 - [0236.lowest-common-ancestor-of-a-binary-tree](./problems/236.lowest-common-ancestor-of-a-binary-tree.md)
 - [0238.product-of-array-except-self](./problems/238.product-of-array-except-self.md) 🆕 
 - [0240.search-a-2-d-matrix-ii](./problems/240.search-a-2-d-matrix-ii.md)

263.ugly-number.js

@@ -95,10 +95,11 @@ leetcode 题解，记录自己的 leetcode 解题之路。
 - [0020.Valid Parentheses](./problems/20.validParentheses.md)
 - [0026.remove-duplicates-from-sorted-array](./problems/26.remove-duplicates-from-sorted-array.md)
 - [0088.merge-sorted-array](./problems/88.merge-sorted-array.md)
-- [0121.best-time-to-buy-and-sell-stock](./problems/121.best-time-to-buy-and-sell-stock.md) 🆕
-- [0122.best-time-to-buy-and-sell-stock-ii](./problems/122.best-time-to-buy-and-sell-stock-ii.md) 🆕
+- [0121.best-time-to-buy-and-sell-stock](./problems/121.best-time-to-buy-and-sell-stock.md)
+- [0122.best-time-to-buy-and-sell-stock-ii](./problems/122.best-time-to-buy-and-sell-stock-ii.md)
 - [0136.single-number](./problems/136.single-number.md)
 - [0167.two-sum-ii-input-array-is-sorted](./problems/167.two-sum-ii-input-array-is-sorted.md)
+- [0172.factorial-trailing-zeroes](./problems/172.factorial-trailing-zeroes.md) 🆕
 - [0169.majority-element](./problems/169.majority-element.md)
 - [0190.reverse-bits](./problems/190.reverse-bits.md)
 - [0191.number-of-1-bits](./problems/191.number-of-1-bits.md)
@@ -107,8 +108,11 @@ leetcode 题解，记录自己的 leetcode 解题之路。
 - [0206.reverse-linked-list](./problems/206.reverse-linked-list.md)
 - [0219.contains-duplicate-ii](./problems/219.contains-duplicate-ii.md)
 - [0226.invert-binary-tree](./problems/226.invert-binary-tree.md)
+- [0263.ugly-number](./problems/263.ugly-number.md) 🆕
 - [0283.move-zeroes](./problems/283.move-zeroes.md)
+- [0342.power-of-four](./problems/342.power-of-four.md) 🆕
 - [0349.intersection-of-two-arrays](./problems/349.intersection-of-two-arrays.md)
+- [0575.distribute-candies](./problems/575.distribute-candies.md) 🆕
 
 
 #### 中等难度

342.power-of-four.js

@@ -0,0 +1 @@
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575.distribute-candies.js

@@ -0,0 +1 @@
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README.en.md

@@ -0,0 +1 @@
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README.md

@@ -0,0 +1 @@
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assets/drawio/172.factorial-trailing-zeroes.drawio

@@ -0,0 +1,76 @@
+
+## 题目地址
+https://leetcode.com/problems/factorial-trailing-zeroes/description/
+
+## 题目描述
+
+```
+Given an integer n, return the number of trailing zeroes in n!.
+
+Example 1:
+
+Input: 3
+Output: 0
+Explanation: 3! = 6, no trailing zero.
+Example 2:
+
+Input: 5
+Output: 1
+Explanation: 5! = 120, one trailing zero.
+Note: Your solution should be in logarithmic time complexity.
+
+```
+
+## 思路
+
+我们需要求解这n个数字相乘的结果末尾有多少个0，由于题目要求log的复杂度，因此暴力求解是不行的。
+
+通过观察，我们发现如果想要结果末尾是0，必须是分解质因数之后，2 和 5 相乘才行，同时因数分解之后发现5的个数远小于2，
+因此我们只需要求解这n数字分解质因数之后一共有多少个5即可.
+
+![172.factorial-trailing-zeroes-2](../assets/problems/172.factorial-trailing-zeroes-2.png)
+
+如图如果n为30，那么结果应该是图中红色5的个数，即7。
+
+![172.factorial-trailing-zeroes-1](../assets/problems/172.factorial-trailing-zeroes-1.png)
+
+我们的结果并不是直接f(n) = n / 5, 比如n为30， 25中是有两个5的。
+类似，n为150，会有7个这样的数字，通过观察我们发现规律`f(n) = n/5 + n/5^2 + n/5^3 + n/5^4 + n/5^5+..`
+
+![172.factorial-trailing-zeroes-3](../assets/problems/172.factorial-trailing-zeroes-3.png)
+
+如果可以发现上面的规律，用递归还是循环实现这个算式就看你的了。
+## 关键点解析
+
+- 数论
+
+
+## 代码
+
+```js
+
+
+/*
+ * @lc app=leetcode id=172 lang=javascript
+ *
+ * [172] Factorial Trailing Zeroes
+ */
+/**
+ * @param {number} n
+ * @return {number}
+ */
+var trailingZeroes = function(n) {
+  // tag: 数论
+  
+  // if (n === 0) return n;
+
+  // 递归： f(n) = n / 5 + f(n / 5)
+  // return Math.floor(n / 5)  + trailingZeroes(Math.floor(n / 5));
+  let count = 0;
+  while (n >= 5) {
+    count += Math.floor(n / 5);
+    n = Math.floor(n / 5);
+  }
+  return count;
+};
+```

assets/drawio/263.ugly-number.drawio

@@ -0,0 +1,92 @@
+## 题目地址
+
+https://leetcode.com/problems/ugly-number/description/
+
+## 题目描述
+
+```
+Write a program to check whether a given number is an ugly number.
+
+Ugly numbers are positive numbers whose prime factors only include 2, 3, 5.
+
+Example 1:
+
+Input: 6
+Output: true
+Explanation: 6 = 2 × 3
+Example 2:
+
+Input: 8
+Output: true
+Explanation: 8 = 2 × 2 × 2
+Example 3:
+
+Input: 14
+Output: false 
+Explanation: 14 is not ugly since it includes another prime factor 7.
+Note:
+
+1 is typically treated as an ugly number.
+Input is within the 32-bit signed integer range: [−231,  231 − 1].
+
+```
+
+## 思路
+
+题目要求给定一个数字，判断是否为“丑陋数”(ugly number), 丑陋数是指只包含质因子2, 3, 5的正整数。
+
+![263.ugly-number](../assets/problems/263.ugly-number.png)
+
+根据定义，我们将给定数字除以2、3、5(顺序无所谓)，直到无法整除。
+如果得到1，说明是所有因子都是2或3或5，如果不是1，则不是丑陋数。
+
+这就好像我们判断一个数字是否为n(n为大于1的正整数)的幂次方一样，我们只需要
+不断除以n，直到无法整除，如果得到1，那么就是n的幂次方。   这道题的不同在于
+它不再是某一个数字的幂次方，而是三个数字（2，3，5），不过解题思路还是一样的。
+
+转化为代码可以是：
+
+```js
+
+  while(num % 2 === 0)   num = num / 2;
+  while(num % 3 === 0)   num = num / 3;
+  while(num % 5 === 0)   num = num / 5;
+
+  return num === 1;
+
+```
+
+> 我下方给出的代码是用了递归实现，只是给大家看下不同的写法而已。
+
+## 关键点
+- 数论
+- 因数分解
+## 代码
+
+```js
+
+/*
+ * @lc app=leetcode id=263 lang=javascript
+ *
+ * [263] Ugly Number
+ */
+/**
+ * @param {number} num
+ * @return {boolean}
+ */
+var isUgly = function(num) {
+  // TAG: 数论
+  if (num <= 0) return false;
+  if (num === 1) return true;
+
+  const list = [2, 3, 5];
+
+  if (list.includes(num)) return true;
+
+  for (let i of list) {
+    if (num % i === 0) return isUgly(Math.floor(num / i));
+  }
+  return false;
+};
+```
+