feat: leetcode 1796

Author: deweyou

README.md

@@ -2,7 +2,7 @@
 
 <p align="center">
 <!-- TOPICS COUNT START -->
-<img src="https://img.shields.io/badge/-进度:560-green" alt="进度:560">
+<img src="https://img.shields.io/badge/-进度:561-green" alt="进度:561">
 <!-- TOPICS COUNT END -->
 <a href="./assets/docs/TOPICS.md"><img src="https://img.shields.io/badge/-题库目录-blue" alt="题库目录"></a>
 <a href="./assets/docs/CATEGORIES.md"><img src="https://img.shields.io/badge/-题库分类-red" alt="题库分类"></a>

assets/data/categories.json

@@ -2831,6 +2831,12 @@
         "path": "./problemset/check-if-one-string-swap-can-make-strings-equal/README.md",
         "difficulty": "简单"
       },
+      {
+        "id": "1796",
+        "title": "字符串中第二大的数字",
+        "path": "./problemset/second-largest-digit-in-a-string/README.md",
+        "difficulty": "简单"
+      },
       {
         "id": "1822",
         "title": "数组元素积的符号",

assets/data/topics.json

@@ -5239,6 +5239,16 @@
     "url": "https://leetcode-cn.com/problems/find-center-of-star-graph/",
     "path": "./problemset/find-center-of-star-graph/README.md"
   },
+  {
+    "id": "1796",
+    "title": {
+      "cn": "字符串中第二大的数字",
+      "en": "second-largest-digit-in-a-string"
+    },
+    "difficulty": "简单",
+    "url": "https://leetcode.cn/problems/second-largest-digit-in-a-string/",
+    "path": "./problemset/second-largest-digit-in-a-string/README.md"
+  },
   {
     "id": "1800",
     "title": {

assets/docs/CATEGORIES.md

@@ -513,6 +513,7 @@
 | 1769. [移动所有球到每个盒子所需的最小操作数](../../problemset/minimum-number-of-operations-to-move-all-balls-to-each-box/README.md) | 中等 |
 | 1773. [统计匹配检索规则的物品数量](../../problemset/count-items-matching-a-rule/README.md) | 简单 |
 | 1790. [仅执行一次字符串交换能否使两个字符串相等](../../problemset/check-if-one-string-swap-can-make-strings-equal/README.md) | 简单 |
+| 1796. [字符串中第二大的数字](../../problemset/second-largest-digit-in-a-string/README.md) | 简单 |
 | 1822. [数组元素积的符号](../../problemset/sign-of-the-product-of-an-array/README.md) | 简单 |
 | 1958. [文件夹操作日志搜集器](../../problemset/crawler-log-folder/README.md) | 简单 |
 | 1961. [检查字符串是否为数组前缀](../../problemset/check-if-string-is-a-prefix-of-array/README.md) | 简单 |

assets/docs/TOPICS.md

@@ -1048,6 +1048,8 @@
 
 [1791. 找出星型图的中心节点](../../problemset/find-center-of-star-graph/README.md)
 
+[1796. 字符串中第二大的数字](../../problemset/second-largest-digit-in-a-string/README.md)
+
 [1800. 最大升序子数组和](../../problemset/maximum-ascending-subarray-sum/README.md)
 
 [1822. 数组元素积的符号](../../problemset/sign-of-the-product-of-an-array/README.md)

problemset/second-largest-digit-in-a-string/README.md

@@ -0,0 +1,58 @@
+# 字符串中第二大的数字
+
+> 难度：简单
+>
+> https://leetcode.cn/problems/second-largest-digit-in-a-string/
+
+## 题目
+
+给你一个混合字符串 `s` ，请你返回 `s` 中 **第二大** 的数字，如果不存在第二大的数字，请你返回 `-1` 。
+
+**混合字符串** 由小写英文字母和数字组成。
+
+### 示例
+
+#### 示例 1：
+
+```
+输入：s = "dfa12321afd"
+输出：2
+解释：出现在 s 中的数字包括 [1, 2, 3] 。第二大的数字是 2 。
+```
+
+#### 示例 2：
+
+```
+输入：s = "abc1111"
+输出：-1
+解释：出现在 s 中的数字只包含 [1] 。没有第二大的数字。
+```
+
+## 解题
+
+```ts 
+/**
+ * 直接遍历
+ * @desc 时间复杂度 O(n) 空间复杂度 O(1)
+ * @param s
+ * @returns
+ */
+export function secondHighest(s: string): number {
+  let first = -1
+  let second = -1
+  for (let i = 0; i < s.length; i++) {
+    const c = s[i]
+    if (c >= '0' && c <= '9') {
+      const num = c.charCodeAt(0) - '0'.charCodeAt(0)
+      if (num > first) {
+        second = first
+        first = num
+      }
+      else if (num < first && num > second) {
+        second = num
+      }
+    }
+  }
+  return second
+}
+```

problemset/second-largest-digit-in-a-string/index.spec.ts

@@ -0,0 +1,15 @@
+import { describe, expect, it } from 'vitest'
+import { secondHighest } from '.'
+
+describe('字符串中第二大的数字', () => {
+  testCase(secondHighest)
+})
+
+function testCase(fn: (s: string) => number) {
+  it.each([
+    ['dfa12321afd', 2],
+    ['abc1111', -1],
+  ])('示例%#', (s, expected) => {
+    expect(fn(s)).toBe(expected)
+  })
+}

problemset/second-largest-digit-in-a-string/index.ts

@@ -0,0 +1,24 @@
+/**
+ * 直接遍历
+ * @desc 时间复杂度 O(n) 空间复杂度 O(1)
+ * @param s
+ * @returns
+ */
+export function secondHighest(s: string): number {
+  let first = -1
+  let second = -1
+  for (let i = 0; i < s.length; i++) {
+    const c = s[i]
+    if (c >= '0' && c <= '9') {
+      const num = c.charCodeAt(0) - '0'.charCodeAt(0)
+      if (num > first) {
+        second = first
+        first = num
+      }
+      else if (num < first && num > second) {
+        second = num
+      }
+    }
+  }
+  return second
+}