DFSでタイムスタンプ
IN = [0 for _ in range(N)]
OUT = [0 for _ in range(N)]
cnt = 0
def DFS(now):
global cnt
IN[now] = cnt
for next in Edge[now]:
cnt += 1
DFS(next)
cnt += 1
OUT[now] = cnt
DFS(0)
IN = [0 for _ in range(N)]
OUT = [0 for _ in range(N)]
cnt = 0
def DFS(now):
global cnt
IN[now] = cnt
for next in Edge[now]:
cnt += 1
DFS(next)
cnt += 1
OUT[now] = cnt
DFS(0)