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Capitalize Matching Substrings

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Your question is Capitalize Matching Substrings. Start with the requirements on the right.

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Problem

The Uber Drivers app receives text containing driver-facing labels and messages. Given a text string and an array of target substrings, find every occurrence of each target and capitalize its first character while preserving the remaining characters.

When matches overlap, apply these rules: process the text from left to right, choose the longest matching target at the current position, replace it, then continue after the replacement. Matching is case-sensitive. Duplicate targets should behave like one target. Empty targets are not included.

Formal Specification

Implement capitalize_substrings(text, patterns).

  • Input: text, a string of ASCII letters, digits, spaces, and punctuation; patterns, an array of non-empty ASCII strings.
  • Output: A string with selected non-overlapping occurrences transformed so their first character is uppercase. The rest of each matched substring remains unchanged.

Constraints

  • 1 <= len(text) <= 10^5
  • 1 <= len(patterns) <= 10^4
  • The total number of characters across all patterns is at most 10^5
  • Every pattern is non-empty
  • All input characters are ASCII
  • Matching is case-sensitive

Function Signature

def capitalize_substrings(text, patterns):
Your solutionPython 3
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