{ "data": { "question": { "questionId": "1756", "questionFrontendId": "1653", "boundTopicId": null, "title": "Minimum Deletions to Make String Balanced", "titleSlug": "minimum-deletions-to-make-string-balanced", "content": "

You are given a string s consisting only of characters 'a' and 'b'​​​​.

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You can delete any number of characters in s to make s balanced. s is balanced if there is no pair of indices (i,j) such that i < j and s[i] = 'b' and s[j]= 'a'.

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Return the minimum number of deletions needed to make s balanced.

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Example 1:

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\nInput: s = "aababbab"\nOutput: 2\nExplanation: You can either:\nDelete the characters at 0-indexed positions 2 and 6 ("aababbab" -> "aaabbb"), or\nDelete the characters at 0-indexed positions 3 and 6 ("aababbab" -> "aabbbb").\n
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Example 2:

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\nInput: s = "bbaaaaabb"\nOutput: 2\nExplanation: The only solution is to delete the first two characters.\n
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Constraints:

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