Python interview question: run-length encoding

MediumArrays and strings

events is a courier app’s event stream, one lowercase letter per event. Replace each run of identical consecutive letters with the letter and the run length, leaving a run of one without a number. Return the compressed string.

def compress_events(events: str) -> str:

Example

• events = 'pppdcc' → 'p3dc2'a single d gets no number
• events = 'dddddddddddd' → 'd12'a length can have several digits

Skills it tests

• String traversal
• Consecutive runs

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