{ "data": { "question": { "questionId": "3487", "questionFrontendId": "3316", "boundTopicId": null, "title": "Find Maximum Removals From Source String", "titleSlug": "find-maximum-removals-from-source-string", "content": "

You are given a string source of size n, a string pattern that is a subsequence of source, and a sorted integer array targetIndices that contains distinct numbers in the range [0, n - 1].

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We define an operation as removing a character at an index idx from source such that:

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Performing an operation does not change the indices of the other characters in source. For example, if you remove 'c' from "acb", the character at index 2 would still be 'b'.

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Return the maximum number of operations that can be performed.

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Example 1:

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Input: source = "abbaa", pattern = "aba", targetIndices = [0,1,2]

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Output: 1

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Explanation:

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We can't remove source[0] but we can do either of these two operations:

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Example 2:

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Input: source = "bcda", pattern = "d", targetIndices = [0,3]

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Output: 2

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Explanation:

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We can remove source[0] and source[3] in two operations.

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Example 3:

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Input: source = "dda", pattern = "dda", targetIndices = [0,1,2]

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Output: 0

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Explanation:

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We can't remove any character from source.

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Example 4:

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Input: source = "yeyeykyded", pattern = "yeyyd", targetIndices = [0,2,3,4]

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Output: 2

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Explanation:

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We can remove source[2] and source[3] in two operations.

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Constraints:

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C# 12 with .NET 8 runtime

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Go 1.23

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