description Problem history Submissions question_mark Qna how_to_vote Vote #4948 upload 36 done 20 how_to_reg 14 되돌리기 가능한 트리 timer 1s memory 256MB upload Attempts 36 times Solved 20 times Solvers 14 people Acceptance Rate 55.6% monitoring Average Runtime 270.4ms Average Memory 18750.1KB Average Code Length 2215.3B No. Submitter Result Time Memory Length Language Submitted