




'''simple docstring'''
def  lowerCamelCase(       SCREAMING_SNAKE_CASE_					,SCREAMING_SNAKE_CASE_    )		->		float:
			return a + b


if __name__ == "__main__":
							_SCREAMING_SNAKE_CASE =	5
							_SCREAMING_SNAKE_CASE =	6
							print(f"""The sum of {a} + {b} is {add(a, b)}""")










'''simple docstring'''
from __future__ import annotations





def  lowerCamelCase(       SCREAMING_SNAKE_CASE_    )		->		Optional[int]:
			global graph, reversed_graph, scc, component, visit, stack
			if visit[u]:
						return
			A_       		=   True
			for v in graph[u]:
						dfs(SCREAMING_SNAKE_CASE_    )
			stack.append(SCREAMING_SNAKE_CASE_    )





def  lowerCamelCase(       SCREAMING_SNAKE_CASE_    )		->		List[Any]:
			global graph, reversed_graph, scc, component, visit, stack
			if visit[u]:
						return
			A_       		=   True
			component.append(SCREAMING_SNAKE_CASE_    )
			for v in reversed_graph[u]:
						dfsa(SCREAMING_SNAKE_CASE_    )





def  lowerCamelCase(       )		->		int:
			global graph, reversed_graph, scc, component, visit, stack
			for i in range(SCREAMING_SNAKE_CASE_    ):
						dfs(SCREAMING_SNAKE_CASE_    )
			A_       		=   [False] * n
			for i in stack[::-1]:
						if visit[i]:
									continue
						A_       		=   []
						dfsa(SCREAMING_SNAKE_CASE_    )
						scc.append(SCREAMING_SNAKE_CASE_    )
			return scc


if __name__ == "__main__":
							# n - no of nodes, m - no of edges
							_SCREAMING_SNAKE_CASE ,						_SCREAMING_SNAKE_CASE =	list(map(int, input().strip().split()))

							_SCREAMING_SNAKE_CASE =	[[] for _ in range(n)]  # graph
							_SCREAMING_SNAKE_CASE =	[[] for i in range(n)]  # reversed graph
							# input graph data (edges)
							for _ in range(m):
														_SCREAMING_SNAKE_CASE ,						_SCREAMING_SNAKE_CASE =	list(map(int, input().strip().split()))
														graph[u].append(v)
														reversed_graph[v].append(u)

							_SCREAMING_SNAKE_CASE =	[]
							_SCREAMING_SNAKE_CASE =	[False] * n
							_SCREAMING_SNAKE_CASE =	[]
							_SCREAMING_SNAKE_CASE =	[]
							print(kosaraju())




