[프로그래머스 lv2] 여행경로 (DFS/파이썬)

https://school.programmers.co.kr/learn/courses/30/lessons/43164

import collections
answer = []
graph = collections.defaultdict(list)

def dfs(s):
    while graph[s]:
        dfs(graph[s].pop(0))

    if not graph[s]:
        answer.append(s)
        return

def solution(tickets):
    
    for a,b in tickets:
        graph[a].append(b)
    for a, b in graph.items():
        graph[a].sort()
        
    dfs("ICN")

    return answer[::-1]