leetcode.com/explore/featured/card/top-interview-questions-easy/94/trees/625/ Explore - LeetCode LeetCode Explore is the best place for everyone to start practicing and learning on LeetCode. No matter if you are a beginner or a master, there are always new topics waiting for you to explore. leetcode.com 첫 번째 시도 ( Fail ) 재귀함수를 써보려고 했는데, 결과적으로는 개별노드의 왼쪽/오른쪽 자식노드만 기준을 만족한다. 문제에 대한 이해가 부족했다. class S..