김민지

from collections import defaultdict def solution(tickets): answer=[] graph=defaultdict(list) for ticket in tickets : graph[ticket[0]].append(ticket[1]) for key in graph.keys(): graph[key].sort(reverse=True) def dfs(): stack=["ICN"] while stack : start=stack[-1] if not graph[start] : answer.append(stack.pop()) else: stack.append(graph[start].pop()) dfs() return answer[::-1]