Most Frequent Call in Logs

Given a list of API call log entries, find the most frequently occurring call. If multiple calls have the same maximum frequency, return the one that appears first in the input.

Example: Input: ["GET /home", "POST /login", "GET /home", "GET /search"] Output: "GET /home"

Follow-ups:

• Return the top K most frequent calls
• Frequency within a sliding time window
• Real-time streaming (Count-Min Sketch for approximate counts)