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: 
#graphの頂点vertex(インデックス、0オリジン)を深さ優先探索。dis_time:最初に訪れた時のtimeを管理するリスト
#fin_time:その頂点に対して、探索が終わった時のtimeを管理するリスト　tmp_time:現在のtime(関数内で変更できるようにリスト)
def DPS(graph,vertex,dis_time,fin_time,tmp_time):
    tmp_time[0]+=1
    dis_time[vertex]=tmp_time[0]
    for i in range(len(graph[0])):
        if(graph[vertex][i] !=0 and dis_time[i]==0):#枝先の頂点が探索済みでなかったら、
            DPS(graph,i,dis_time,fin_time,tmp_time)
    
    tmp_time[0]+=1
    fin_time[vertex]=tmp_time[0]



#グラフの作成
n=int(input())
graph=[[0]*n for loop in range(n)]
for loop in range(n):
    tmp_ope=list(map(int,input().split()))
    for j in range(tmp_ope[1]):
        graph[tmp_ope[0]-1][tmp_ope[j+2]-1]=1


dis_time=[0]*n
fin_time=[0]*n
tmp_time=[0]
for i in range(n):
    if(dis_time[i]==0):
        DPS(graph,i,dis_time,fin_time,tmp_time)

for i in range(n):
    print(f"{i+1} {dis_time[i]} {fin_time[i]}")

Python: def main():
    num = int(input())
    Dst = [None for i in range(num + 1)]
    Fst = [0] * (num + 1)
    Lst = Fst[:]
    S = []

    for n in range(1, num+1):
        a = list(map(int,input().split()))
        u = a[0]
        if a[1] > 0:
            Dst[u] = a[2:]
            Dst[u].reverse()

    cnt = 1
    S.append(1)
    Fst[1] = 1
    while(len(S) > 0):
        cnt += 1
        u = S.pop()
        if Dst[u] is not None and len(Dst[u]) > 0:
            u1 = Dst[u].pop()
            if Fst[u1] == 0:
                S.append(u)
                S.append(u1)
                Fst[u1] = cnt
            else:
                Lst[u] = cnt
        else:
            Lst[u] = cnt

    for n in range(1, num+1):
        print("{} {} {}".format(n,Fst[n],Lst[n]))

if __name__ == '__main__':
    main()

Python: n = int(input())
G = [[] for _ in range(n)]
u1 = 0
for _ in range(n):
    u, k, *v = [int(i) for i in input().split()]
    G[u - 1] = v
    if k != 0 and u1 == 0:
        u1 = u

time = 1
u = u1
D = []
F = []
out = [[i+1, 0, 0] for i in range(n)]
T = []
while True:
    if u not in D:
        out[u - 1][1] = time
        D.append(u)
        T.append(u)

    for f in F:
        if f in G[u - 1]:
            idx = G[u - 1].index(f)
            del G[u - 1][idx]

    if G[u - 1] == []:
        time += 1
        out[T.pop() - 1][2] = time
        F.append(u)
        if T == []:
            if len(D) == n:
                break
            else:
                for ni in range(n):
                    if ni + 1 not in D:
                        u = ni + 1
                        break
                time += 1
                continue
        else:
            u = T[-1]
    else:
        if G[u - 1][0] != u:
            time += 1
        u = G[u - 1].pop(0)

for ni in range(n):
    print(*out[ni])

Python: from collections import deque


def dfs(root):
    time = 1
    stack.append(root)
    color[root] = 'gray'
    arrive[root] = time
    time += 1

    while len(stack) > 0:
        node = stack[-1]
        for next in range(n):
            if adjMat[node][next] == 1:
                if color[next] == 'white':
                    color[next] = 'gray'
                    arrive[next] = time
                    time += 1
                    stack.append(next)
                    break
        # In case there in no adjacent node whose color is white
        color[node] = 'black'
        finish[node] = time
        time += 1
        stack.pop()


n = int(input())

adjMat = [[0] * n for _ in range(n)]
color = ['white'] * n
stack = deque()
arrive = [0] * n
finish = [0] * n

for _ in range(n):
    adj = list(map(int, input().split()))
    i = adj[0]
    v = adj[2:]
    for j in v:
        adjMat[i - 1][j - 1] = 1

dfs(0)

for i in range(n):
    out = ''
    out += '{} {} {}'.format(i+1, arrive[i], finish[i])
    print(out)

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-1][v-1] == 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: def main():
    import sys
    N = int(sys.stdin.readline())
    L1 = [list(map(int, sys.stdin.readline().split())) for _ in range(N)]
    #print(L1)
    edge = [[] for _ in range(N+1)]
    for row in L1:
        for ele in row[2:]:
            edge[row[0]].append(ele)
            #edge[ele].append(row[0])

    #print(edge)
    sys.setrecursionlimit(1000)
    
    go = [-1 for _ in range(N+1)]
    go[0], go[1] =0, 1
    back = [-1 for _ in range(N+1)]
    
    d = [1]
    def dfs(p):
        if edge[p]:
            for c in edge[p]:
                if go[c]==-1:
                    d[0]+=1
                    go[c] = d[0]
                    dfs(c)
        
        #抜ける順
        d[0]+=1
        back[p] =d[0]
                
    dfs(1)
    for i in range(2, N+1):
        if go[i] ==-1:
            d[0]+=1
            go[i] = d[0]
            dfs(i)
    for i in range(1, N+1):
        print(i, go[i], back[i])




if __name__=='__main__':
    main()