[LeetCode][Python3] 207. Course Schedule

Problem :

https://leetcode.com/problems/course-schedule/

My Solution :

class Solution:

def canFinish(self, numCourses, prerequisites):

def dfs(vertex):

if visited[vertex]:

return True

if visited[vertex] == False:

return False

visited[vertex] = False

for prerequisite in graph[vertex]:

if not dfs(prerequisite):

return False

visited[vertex] = True

return True

visited = [None]*numCourses

graph = [list() for _ in range(numCourses)]

for vertex, prerequisite in prerequisites:

graph[vertex].append(prerequisite)

for vertex in range(numCourses):

if not dfs(vertex):

return False

return True

Comment :

전형적인 그래프 탐색 문제인데 볼 때마다 새롭고 한 번에 잘 안 풀리네 ㅠㅠ