Go: package main

/*
深さ優先探索
*/

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

func main() {
	scanner := makeScanner(8192)
	n := eGetInt(scanner)
	g := make([][]int, n+1)
	for i := 1; i < n+1; i++ {
		ints := eGetInts(scanner)
		num, vcount := ints[0], ints[1]
		g[i] = make([]int, vcount)
		for j := 0; j < vcount; j++ {
			g[num][j] = ints[j+2]
		}
	}
	hist := make([]struct{ d, f int }, n+1)
	t := 0
	var visit func(int)
	visit = func(num int) {
		if hist[num].d == 0 {
			stack := []int{}
			t++
			hist[num].d = t
			stack = append(stack, num)
			for len(stack) > 0 {
				// トップを訪問する
				top := stack[len(stack)-1]
				for i := 0; i < len(g[top]); i++ {
					if hist[g[top][i]].d == 0 {
						t++
						hist[g[top][i]].d = t
						stack = append(stack, g[top][i])
						goto endloop
					}
				}
				// 訪問場所がなくなったら
				// pop
				stack = stack[0 : len(stack)-1]
				t++
				hist[top].f = t
			endloop:
			}
		}
	}
	for i := 1; i < n+1; i++ {
		visit(i)
	}
	for i := 1; i < n+1; i++ {
		fmt.Println(i, hist[i].d, hist[i].f)
	}
}

////////////////////////////////////////////////////////////////////////////////
// ライブラリ
////////////////////////////////////////////////////////////////////////////////
func makeScanner(maxByte int) *bufio.Scanner {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Buffer(make([]uint8, 0, 8192), maxByte)
	return scanner
}
func makeWordScanner() *bufio.Scanner {
	scanner := makeScanner(8192)
	scanner.Split(bufio.ScanWords)
	return scanner
}
func eGetLine(r *bufio.Scanner) string {
	if r.Scan() {
		return r.Text()
	}
	err := r.Err()
	if err != nil {
		log.Fatal(err)
	}
	// EOF
	return ""
}
func eGetInt(r *bufio.Scanner) int {
	line := eGetLine(r)
	return eAtoi(line)
}
func eGetInt64(r *bufio.Scanner) int64 {
	line := eGetLine(r)
	return eAtoInt64(line)
}
func eGetFields(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Fields(line)
}
func eGetInts(r *bufio.Scanner) []int {
	fields := eGetFields(r)
	ints := make([]int, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoi(fields[i])
	}
	return ints
}
func eGetInt64s(r *bufio.Scanner) []int64 {
	fields := eGetFields(r)
	ints := make([]int64, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoInt64(fields[i])
	}
	return ints
}
func eGetChars(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Split(line, "")
}
func eAtoi(s string) int {
	n, err := strconv.Atoi(s)
	if err != nil {
		log.Fatal(err)
	}
	return n
}
func eAtoInt64(s string) int64 {
	n, err := strconv.ParseInt(s, 10, 64)
	if err != nil {
		log.Fatal(err)
	}
	return n
}

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

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

WHITE = 0
GRAY = 1
BLACK = 2
color, d, f = [WHITE for i in range(n)]
t = 1
for u in range(n):
    if (color[u] == WHITE):
        visit(u)
for u in range(n):
    print(str(u+1), str(d[u]), str(f[u]), sep = " ")

Python: n=0
t=1
def adjacent_matrix():
    global n
    n=int(input())
    v=[]
    array=[]
    for i in range(n):
        zero=[0 for i in range(n)]
        a=list(map(int,input().split()))
        a=a[2:]
        for j in a:
            zero[j-1]=1
        array.append(zero)
    return array
def dfs(array,i,d,f):
    global t
    if i == n:
        return
    else:
        if(d[i] == 0):
            d[i] = t
            t += 1
            for (j,x) in enumerate(array[i]):
                if x == 1:
                    dfs(array,j,d,f)
            f[i] = t
            t += 1
    return 


def main():
    array=adjacent_matrix()
    d=[0 for i in range(n)]
    f=[0 for i in range(n)]
    for i in range(n):
        dfs(array,i,d,f)
    for i in range(n):
        print("{} {} {}".format(i+1,d[i],f[i]))

if __name__ == "__main__":
    main()

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

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

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

Python: n=int(input())
g=[]
for i in range(n):
    u,k,*varray= map(int,input().split())
    g.append(varray)

time = 1
d= [-1]* n
f= [-1]* n

def dfs(src):
    global time
    d[src]= time
    time+=1
    for i in g[src]:
        if d[i-1]== -1:
            dfs(i-1)
    f[src]= time
    time+=1

for i in range(n):
    if d[i]== -1:
        dfs(i)
for i in range(n):
    print(i+1,d[i],f[i])

Python: N = int(input())
adj_list = [ [] for _ in range(N+1) ]
for _ in range(N):
  lst = list(map(int,input().split()))
  node = lst[0]
  if lst[1] != 0:
    adj_list[node] = lst[2:]


visited = [False] * (N+1)
arrived = [-1] * (N+1)
left = [-1] * (N+1)

time = 0
def dfs(node):
  global time

  arrived[node] = time
  visited[node] = True

  for nei in adj_list[node]:
    if not visited[nei]:
      time += 1
      dfs(nei)
  else:
    time += 1
    left[node] = time

for i in range(1, N+1):
  if not visited[i]:
    time += 1
    dfs(i)

for i in range(1, N+1):
  print(i, arrived[i], left[i])

Python: # coding: utf-8
def depth(i, adj, Dep, Arr, times):
    if Dep[i-1]:
        return times
    Dep[i-1]=times
    times+=1
    # t=[depth(j, adj, Dep, f, times) j in adj[i-1]]
    for j in adj[i-1]:
        times=depth(j, adj, Dep, Arr, times)
    Arr[i - 1]=times
    times+=1
    return times


n=int(input())
adj=[list(map(int, input().split()))[2:] for i in range(n)]

d,f=[0]*n,[0]*n

t=1

dlist=[i for i in range(n) if d[i]==0]

for i in dlist:
    t = depth(i + 1, adj, d, f, t)

for i, df in enumerate(zip(d, f)):
    print(i + 1, *df)

Python: def main():

    inf = 1000000007
    n = int(input())
    e = [[] for _ in range(n)]
    d = [inf]*n
    f = [inf]*n
    step = 1

    def dfs(v):
        nonlocal step
        d[v] = step
        step+=1
        for u in e[v]:
            if d[u] == inf:dfs(u)
        f[v] = step
        step +=1

    e = [[] for _ in range(n)]
    for i in range(n):
        m = list(map(int,input().split()))
        for j in range(2,len(m)):
            e[m[0]-1].append(m[j]-1)
    for i in range(n):
        if d[i]==inf:dfs(i)
    for i in range(n):
        print (i+1,d[i],f[i])

if __name__ == '__main__':
    main()

Python: import collections,sys
def I(): return int(sys.stdin.readline().rstrip())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))
n = I()
ukv = [LI() for _ in range(n)]
graph = {i:collections.deque() for i in range(1,n+1)} #1_indexed
for x in ukv:
    u,k,*v = x
    for y in v:
        graph[u].append(y)
seen = [0]*(n+1) #1_indexed
stack = []
time = 0
seentime = [0]*(n+1) #1_indexed
donetime = [0]*(n+1) #1_indexed
def dfs(j):
    global time
    seen[j] = 1
    stack.append(j)
    time += 1
    seentime[j] = time
    while stack:
        s = stack[-1]
        if not graph[s]:
            stack.pop()
            time += 1
            donetime[s] = time
            continue
        g_NO = graph[s].popleft()
        if seen[g_NO]:
            continue
        seen[g_NO] = 1
        stack.append(g_NO)
        time += 1
        seentime[g_NO] = time
for j in range(1,n+1):
    if seen[j]:
        continue
    dfs(j)
for k,a,b in zip(range(1,n+1),seentime[1:],donetime[1:]):
    print(k,a,b)