1436. 旅行终点站

class Solution:
    def destCity(self, paths: List[List[str]]) -> str:
        start, end = [], []
        for s, e in paths:
            start.append(s)
            end.append(e)

        for x in end:
            if x not in start:
                return x

class Solution:
    def destCity(self, paths: List[List[str]]) -> str:
        citiesA = {path[0] for path in paths}
        return next(path[1] for path in paths if path[1] not in citiesA)