{ "data": { "question": { "questionId": "3337", "questionFrontendId": "3084", "categoryTitle": "Algorithms", "boundTopicId": 2689641, "title": "Count Substrings Starting and Ending with Given Character", "titleSlug": "count-substrings-starting-and-ending-with-given-character", "content": "

You are given a string s and a character c. Return the total number of substrings of s that start and end with c.

\n\n

 

\n

Example 1:

\n\n
\n

Input: s = "abada", c = "a"

\n\n

Output: 6

\n\n

Explanation: Substrings starting and ending with "a" are: "abada", "abada", "abada", "abada", "abada", "abada".

\n
\n\n

Example 2:

\n\n
\n

Input: s = "zzz", c = "z"

\n\n

Output: 6

\n\n

Explanation: There are a total of 6 substrings in s and all start and end with "z".

\n
\n\n

 

\n

Constraints:

\n\n\n", "translatedTitle": "统计以给定字符开头和结尾的子字符串总数", "translatedContent": "

给你一个字符串 s 和一个字符 c 。返回在字符串 s 中并且以 c 字符开头和结尾的非空子字符串的总数。

\n\n

 

\n\n

示例 1：

\n\n
\n

输入：s = \"abada\", c = \"a\"

\n\n

输出：6

\n\n

解释：以 \"a\" 开头和结尾的子字符串有： \"abada\"、\"abada\"、\"abada\"、\"abada\"、\"abada\"、\"abada\"。

\n
\n\n

示例 2：

\n\n
\n

输入：s = \"zzz\", c = \"z\"

\n\n

输出：6

\n\n

解释：字符串 s 中总共有 6 个子字符串，并且它们都以 \"z\" 开头和结尾。

\n
\n\n

 

\n\n

提示：

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