{ "data": { "question": { "questionId": "392", "questionFrontendId": "392", "boundTopicId": null, "title": "Is Subsequence", "titleSlug": "is-subsequence", "content": "

Given two strings s and t, return true if s is a subsequence of t, or false otherwise.

\n\n

A subsequence of a string is a new string that is formed from the original string by deleting some (can be none) of the characters without disturbing the relative positions of the remaining characters. (i.e., "ace" is a subsequence of "abcde" while "aec" is not).

\n\n

 

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Example 1:

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Input: s = \"abc\", t = \"ahbgdc\"\nOutput: true\n

Example 2:

\n
Input: s = \"axc\", t = \"ahbgdc\"\nOutput: false\n
\n

 

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Constraints:

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\nFollow up: Suppose there are lots of incoming s, say s1, s2, ..., sk where k >= 109, and you want to check one by one to see if t has its subsequence. 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OpenJDK 17. Java 8 features such as lambda expressions and stream API can be used.

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Python 2.7.12.

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C# 10 with .NET 6 runtime

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Node.js 16.13.2.

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