Longest streak of active days

Python data engineering interview problem. Difficulty: intermediate. Pattern: Sliding Window. About 15 minutes. Part of the Pro drill bank.

A product's daily active flag is a list of 0/1 (or False/True). Retention wants the longest consecutive streak of active days.

Return the longest run of consecutive active days.

Requirements

• A streak breaks on an inactive day.
• Return a length, not the slice itself, unless tests say otherwise.

Constraints

• flags: a sequence of active/inactive markers.
• All inactive: streak 0.
• All active: streak is the full length.

Examples

Input: longest_active_streak([1, 1, 0, 1, 1, 1]) Output: 3 This input follows the stated rules and produces this output.

Topics: lakebench, python, sliding-window.

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