Add solution 0299

Author: halfrost

README.md

@@ -1,4 +1,4 @@
-# [299. Bulls and Cows](https://leetcode-cn.com/problems/bulls-and-cows/)
+# [299. Bulls and Cows](https://leetcode.com/problems/bulls-and-cows/)
 
 
 ## 题目
@@ -72,12 +72,14 @@ Output: "1A0B"
 
 ## 解题思路
 
-- 计算下标一致并且对应下标的元素一致的个数，即x
-- secret和guess分别去除x个公牛的元素,剩下secret和guess求共同的元素个数就是y
-- 把x， y转换成字符串，分别与"A"和"B"进行拼接返回结果
+- 计算下标一致并且对应下标的元素一致的个数，即 x
+- secret 和 guess 分别去除 x 个公牛的元素,剩下 secret 和 guess 求共同的元素个数就是 y
+- 把 x， y 转换成字符串，分别与 "A" 和 "B" 进行拼接返回结果
 
 ## 代码
+
 ```go
+
 package leetcode
 
 import "strconv"

leetcode/0299.Bulls-and-Cows/README.md

@@ -116,5 +116,5 @@ func (this *Codec) deserializeHelper() *TreeNode {
 ----------------------------------------------
 <div style="display: flex;justify-content: space-between;align-items: center;">
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+<p><a href="https://books.halfrost.com/leetcode/ChapterFour/0200~0299/0299.Bulls-and-Cows/">下一页➡️</a></p>
 </div>

website/content/ChapterFour/0200~0299/0297.Serialize-and-Deserialize-Binary-Tree.md

@@ -0,0 +1,121 @@
+# [299. Bulls and Cows](https://leetcode.com/problems/bulls-and-cows/)
+
+
+## 题目
+
+You are playing the Bulls and Cows game with your friend.
+
+You write down a secret number and ask your friend to guess what the number is. When your friend makes a guess, you provide a hint with the following info:
+
+The number of "bulls", which are digits in the guess that are in the correct position.
+The number of "cows", which are digits in the guess that are in your secret number but are located in the wrong position. Specifically, the non-bull digits in the guess that could be rearranged such that they become bulls.
+Given the secret number secret and your friend's guess guess, return the hint for your friend's guess.
+
+The hint should be formatted as "xAyB", where x is the number of bulls and y is the number of cows. Note that both secret and guess may contain duplicate digits.
+
+**Example 1:**
+
+```
+Input: secret = "1807", guess = "7810"
+Output: "1A3B"
+Explanation: Bulls are connected with a '|' and cows are underlined:
+"1807"
+  |
+"7810"
+```
+
+**Example 2:**
+
+```
+Input: secret = "1123", guess = "0111"
+Output: "1A1B"
+Explanation: Bulls are connected with a '|' and cows are underlined:
+"1123"        "1123"
+  |      or     |
+"0111"        "0111"
+Note that only one of the two unmatched 1s is counted as a cow since the non-bull digits can only be rearranged to allow one 1 to be a bull.
+```
+
+**Example 3:**
+
+```
+Input: secret = "1", guess = "0"
+Output: "0A0B"
+```
+
+**Example 4:**
+
+```
+Input: secret = "1", guess = "1"
+Output: "1A0B"
+```
+
+**Constraints:**
+
+- 1 <= secret.length, guess.length <= 1000
+- secret.length == guess.length
+- secret and guess consist of digits only.
+
+## 题目大意
+
+你在和朋友一起玩 猜数字（Bulls and Cows）游戏，该游戏规则如下：
+
+写出一个秘密数字，并请朋友猜这个数字是多少。朋友每猜测一次，你就会给他一个包含下述信息的提示：
+
+猜测数字中有多少位属于数字和确切位置都猜对了（称为 "Bulls", 公牛），
+有多少位属于数字猜对了但是位置不对（称为 "Cows", 奶牛）。也就是说，这次猜测中有多少位非公牛数字可以通过重新排列转换成公牛数字。
+给你一个秘密数字secret 和朋友猜测的数字guess ，请你返回对朋友这次猜测的提示。
+
+提示的格式为 "xAyB" ，x 是公牛个数， y 是奶牛个数，A 表示公牛，B表示奶牛。
+
+请注意秘密数字和朋友猜测的数字都可能含有重复数字。
+
+## 解题思路
+
+- 计算下标一致并且对应下标的元素一致的个数，即 x
+- secret 和 guess 分别去除 x 个公牛的元素,剩下 secret 和 guess 求共同的元素个数就是 y
+- 把 x， y 转换成字符串，分别与 "A" 和 "B" 进行拼接返回结果
+
+## 代码
+
+```go
+
+package leetcode
+
+import "strconv"
+
+func getHint(secret string, guess string) string {
+	cntA, cntB := 0, 0
+	mpS := make(map[byte]int)
+	var strG []byte
+	n := len(secret)
+	var ans string
+	for i := 0; i < n; i++ {
+		if secret[i] == guess[i] {
+			cntA++
+		} else {
+			mpS[secret[i]] += 1
+			strG = append(strG, guess[i])
+		}
+	}
+	for _, v := range strG {
+		if _, ok := mpS[v]; ok {
+			if mpS[v] > 1 {
+				mpS[v] -= 1
+			} else {
+				delete(mpS, v)
+			}
+			cntB++
+		}
+	}
+	ans += strconv.Itoa(cntA) + "A" + strconv.Itoa(cntB) + "B"
+	return ans
+}
+```
+
+
+----------------------------------------------
+<div style="display: flex;justify-content: space-between;align-items: center;">
+<p><a href="https://books.halfrost.com/leetcode/ChapterFour/0200~0299/0297.Serialize-and-Deserialize-Binary-Tree/">⬅️上一页</a></p>
+<p><a href="https://books.halfrost.com/leetcode/ChapterFour/0300~0399/0300.Longest-Increasing-Subsequence/">下一页➡️</a></p>
+</div>

website/content/ChapterFour/0200~0299/0299.Bulls-and-Cows.md

@@ -82,6 +82,6 @@ func lengthOfLIS1(nums []int) int {
 
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 <div style="display: flex;justify-content: space-between;align-items: center;">
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