From logs, find the most frequent event sequence

You are given time-ordered logs. Each log has user_id and event. For each user, build the event stream in chronological order (events may repeat). Define a length-3 event sequence as any consecutive triple (e1,e2,e3). Count all length-3 sequences generated by all users and output the most frequent sequence and its count. Break ties by lexicographically smallest triple. Input First line: integer n Next n lines: user_id event Logs are globally time-sorted; ties follow input order. Output One line: e1 e2 e3 count Constraints 1 <= n <= 2e5 user_id and event are whitespace-free strings Example Input: 7 u1 a u1 b u1 c u1 a u2 a u2 b u2 c Output: a b c 2 Example Input 7 u1 a u1 b u1 c u1 a u2 a u2 b u2 c Output a b c 2