是只有肥肥被這題搞的要死嗎？ 吐了== 一次要肥肥寫我不會寫的LCA 還要肥肥處理python DFS字串concate遇到的MLE 我真的不會寫程式:( def getDirections(self, root: Optional[TreeNode], startValue: int, destValue: int) -> str: LCA = None def findLCA(root) -> bool: nonlocal LCA if root is None: return False left_contains = findLCA(root.left) right_contains = findLCA(root.right) current_is_target = root.val == startValue or root.val == destValue if current_is_target and (left_contains or right_contains): LCA = root return True if left_contains and right_contains: LCA = root return True return current_is_target or left_contains or right_contains findLCA(root) if LCA is None: return "" def findPath(root, target, path): if root is None: return False if root.val == target: return True path.append("L") if findPath(root.left, target, path): return True path.pop() path.append("R") if findPath(root.right, target, path): return True path.pop() return False start_path = [] dest_path = [] findPath(LCA, startValue, start_path) findPath(LCA, destValue, dest_path) return "U" * len(start_path) + "".join(dest_path) -- ※ 發信站: 批踢踢實業坊(ptt.cc), 來自: 125.229.37.69 (臺灣) ※ 文章網址: https://www.ptt.cc/bbs/Marginalman/M.1721144361.A.9E3.html