{ "data": { "question": { "questionId": "2341", "questionFrontendId": "2255", "boundTopicId": null, "title": "Count Prefixes of a Given String", "titleSlug": "count-prefixes-of-a-given-string", "content": "

You are given a string array words and a string s, where words[i] and s comprise only of lowercase English letters.

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Return the number of strings in words that are a prefix of s.

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A prefix of a string is a substring that occurs at the beginning of the string. A substring is a contiguous sequence of characters within a string.

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Example 1:

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\nInput: words = ["a","b","c","ab","bc","abc"], s = "abc"\nOutput: 3\nExplanation:\nThe strings in words which are a prefix of s = "abc" are:\n"a", "ab", and "abc".\nThus the number of strings in words which are a prefix of s is 3.
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Example 2:

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\nInput: words = ["a","a"], s = "aa"\nOutput: 2\nExplanation:\nBoth of the strings are a prefix of s. \nNote that the same string can occur multiple times in words, and it should be counted each time.
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Constraints:

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