# Highlight Overlapping Phrases in a Sentence Given a sentence such as `The quick brown fox jumps over the lazy dog.` and phrases such as `quick brown` and `brown fox jumps`, design a function that returns the sentence with every character covered by any exact phrase match highlighted. The rendering markers are configurable; focus on identifying and merging covered ranges so overlaps produce one continuous highlighted region. ### Constraints & Assumptions - Matching is case-sensitive and phrases may overlap. - The original sentence, spacing, and punctuation must be preserved. - Empty phrases are ignored. ### Clarifying Questions to Ask - Should every occurrence of each phrase be highlighted? - Can one match begin inside another, and should adjacent ranges merge? ```hint Protect the original text Test a phrase inside another phrase, phrases that only touch, and a repeated phrase; every source character must appear exactly once in the rendered output. ``` ### What a Strong Answer Covers - Correct discovery of all occurrences, including overlaps. - Stable interval sorting and merging without changing the source text. - Complexity trade-offs between repeated search and multi-pattern matching. ### Follow-up Questions - How would you handle millions of phrases? - How would case-insensitive Unicode matching affect offsets?