Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

/***************************************************************
stackによる深さ優先探索を実装する。
***************************************************************/

const (
	N     = 100
	WHITE = 0
	GRAY  = 1
	BLACK = 2
)

var (
	n            int
	Adj          [N][N]int
	statusColor  [N]int
	discoverTime [N]int
	finishTime   [N]int
	clock        int
	nt           [N]int
)

/***************************************************************
Stackの定義:
- field
	container: ノードの格納されたスライス
	sp: スタックポインタ
- method
	size(): スタックに積まれているノードの個数を返す
	top(): スタックの一番上に積まれているノードを返す
	isEmpty(): スタックが空かどうかを返す
	pop(): スタックの要素をポップし削除する
	push(): スタックに要素を積む
***************************************************************/

type Stack struct {
	container []int
	sp        int
}

func (s *Stack) size() int {
	return len(s.container)
}

func (s *Stack) top() int {
	return s.container[s.sp]
}

func (s *Stack) isEmpty() bool {
	return s.sp == 0
}

func (s *Stack) pop() int {
	_pop := func() {
		s.container = s.container[:len(s.container)-1]
	}
	defer _pop()
	if s.isEmpty() {
		panic("There is no elements in stack!")
	}
	s.sp--
	return s.container[s.sp]
}

func (s *Stack) push(n int) {
	s.sp++
	s.container[s.sp] = n
}

func next(u int) int {
	for v := nt[u]; v < n; v++ {
		nt[u] = v + 1
		if Adj[u][v] == 1 {
			return v
		}
	}
	return -1
}

func _DFS(target int) {
	for i := 0; i < n; i++ {
		nt[i] = 0
	}
	stack := new(Stack)
	stack.container = make([]int, N+1)
	stack.push(target)
	statusColor[target] = GRAY
	clock++
	discoverTime[target] = clock
	for !stack.isEmpty() {
		u := stack.top()
		v := next(u)
		if v != -1 {
			if statusColor[v] == WHITE {
				statusColor[v] = GRAY
				clock++
				discoverTime[v] = clock
				stack.push(v)
			}
		} else {
			stack.pop()
			statusColor[u] = BLACK
			clock++
			finishTime[u] = clock
		}
	}
}

func DFS() {
	for i := 0; i < n; i++ {
		statusColor[i] = WHITE
		nt[i] = 0
	}
	clock = 0
	for i := 0; i < n; i++ {
		if statusColor[i] == WHITE {
			_DFS(i)
		}
	}
	for i := 0; i < n; i++ {
		fmt.Printf("%d %d %d\n", i+1, discoverTime[i], finishTime[i])
	}
}

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Split(bufio.ScanWords)
	scanner.Scan()
	n, _ = strconv.Atoi(scanner.Text())
	for i := 0; i < n; i++ {
		for j := 0; j < n; j++ {
			Adj[i][j] = 0
		}
	}
	for i := 0; i < n; i++ {
		scanner.Scan()
		u, _ := strconv.Atoi(scanner.Text())
		scanner.Scan()
		k, _ := strconv.Atoi(scanner.Text())
		u--
		for j := 0; j < k; j++ {
			scanner.Scan()
			v, _ := strconv.Atoi(scanner.Text())
			v--
			Adj[u][v] = 1
		}
	}

	DFS()
}

Python: def d(u):
 global t
 C[u]=0;t+=1;D[u]=t
 for v in R:
  if M[u][v]and C[v]:d(v)
 t+=1;F[u]=t
N=int(input());R=range(N)
M=[[0]*N for _ in R]
for e in[input().split()for _ in R]:
 for v in e[2:]:M[int(e[0])-1][int(v)-1]=1
C,D,F=[1]*N,[0]*N,[0]*N
t=0
for i in R:
 if C[i]:d(i)
for i in R:print(i+1,D[i],F[i])

Python: n = int(input())
a = [None]
for i in range(n):
    adj = list(map(int,input().split()))
    a.append(adj[2:])
    
s = [None]
for i in range(1, n + 1):
    s.append([False, i])
    
time = 0

def dfs(u):
    global time
    s[u][0] = True
    time += 1
    s[u].append(time)
    
    for v in a[u]:
        if s[v][0] == False:
            dfs(v)
            
    time += 1
    s[u].append(time)
    
for i in range(1,n+1):
    if s[i][0] == False:
        dfs(i)
        
for x in s[1:]:
    print(*x[1:])

Python: from collections import deque

seen=[]
first_order =[]
last_order = []

def dfs(g, v, first_ptr, last_ptr):
    first_ptr=first_ptr+1
    last_ptr=first_ptr
    
    first_order[v] = first_ptr
    seen[v]=True 
    for next_v in g[v]:
        if seen[next_v]:
            continue
        first_ptr, last_ptr=dfs(g, next_v, first_ptr, last_ptr)
    last_ptr=last_ptr+1
    first_ptr=last_ptr

    last_order[v] = last_ptr
    return first_ptr, last_ptr

icase=1
if icase==0:
    n,m=map(int,input().split())
    g = [deque([]) for _ in range(n + 1)]
    for i in range(m):
        a,b=map(int,input().split())
        g[a].append(b)
#        g[b].append(a) # 無向グラフ
elif icase==1:        
    n=int(input())
    u=[0]*n
    k=[0]*n
#    v=[[] for i in range(n)]
    g = [deque([]) for _ in range(n + 1)]
    for i in range(n):
        ai=list(map(int,input().split()))
        u[i]=ai[0]
        k[i]=ai[1]
        g[i]=deque(ai[2:])
        for j in range(len(g[i])):
            g[i][j]-=1    
elif icase==2:
    n=6
    u=[1,2,3,4,5,6]
    k=[2,2,1,1,1,0]
    g = [deque([]) for _ in range(n + 1)]

    g[0]=deque([1,2])
    g[1]=deque([2,3])
    g[2]=deque([4])
    g[3]=deque([5])
    g[4]=deque([5])
    g[5]=deque([])
    g[5]=deque()

seen=[False]*n
first_ptr=0
last_ptr=0
first_order =[-1]*n
last_order = [-1]*n

for v in range(n):
    if seen[v]:
        continue
    else:
        first_ptr, last_ptr=dfs(g,v,first_ptr, last_ptr)

for v in range(n):
    print(v+1,first_order[v],last_order[v])

Python: def MAIN():
    n = int(input())
    ans = [[i, 0, 0] for i in range((n + 1))]
    G = [[] for _ in range((n + 1))]
    for _ in range(n):
        u, k, *v = map(int, input().split())
        G[u] = v
    cnt = 1
    def dfs(u):
        nonlocal ans
        if ans[u][1] != 0:
            return
        nonlocal cnt
        ans[u][1] = cnt
        cnt += 1
        for v in G[u]:
            dfs(v)
        ans[u][2] = cnt
        cnt += 1
    dfs(1)
    for i in range(1, n + 1):
        print(" ".join(map(str, ans[i])))
MAIN()

Python: WHITE = 0
GRAY = 1
BLACK = 2
color, d, f = [WHITE for i in range(n)]
t = 1

def visit(u):
    color[u] = GRAY
    d[u] += t
    t += 1
    for v in range(n):
        if (M[u-1][v-1] == 0):
            continue
        if (color[v] == WHITE):
            visit(v)
    color[u] = BLACK
    f[u] = t
    t += 1

for u in range(n):
    if (color[u] == WHITE):
        visit(u)
for u in range(n):
    print(u+1, d[u], f[u], sep = " ", end ="\n")

n = int(input())
M = [[[0] for i in range(n)] for i in range(n)]
for i in range(n):
    temp = list(map(int, input().split()))
    for i in range(temp[1]):
        M[temp[0]-1][temp[i+2]-1] = 1

Python: n = int(raw_input())

d = [0 for i in range(n)]
f = [0 for i in range(n)]
a = [[0 for i in range(n)] for j in range(n)]
st = [0 for i in range(n)]
time = [0]
G = [0 for i in range(n)]

def dfs_visit(s):
    st[s] = 1
    time[0] += 1
    d[s] = time[0]
    
    for k in range(n):  
      if a[s][k] == 1 and st[k] == 0:
          dfs_visit(k)
    time[0] += 1
    f[s] = time[0]

def main():
    for s in range(n):
        if st[s] == 0:
            def_visit(s)
    for s in range(n):
        print(s+1,d[s],f[s]) 

for i in range(n):
  G = map(int, raw_input().split())
  for j in range(G[1]):
    v[G[0]-1][G[2+j]-1] = 1
   
main()