Problem:
Splice

For $n$ lists $L_i$ $(i = 0, 1, ..., n-1)$, perform a sequence of the following operations.

insert($t$, $x$): Insert an integer $x$ at the end of $L_t$.

dump($t$): Print all elements in $L_t$.

splice($s$, $t$):　Transfer elements of $L_s$ to the end of $L_t$. $L_s$ becomes empty.

In the initial state, $L_i$ $(i = 0, 1, ..., n-1)$ are empty.

Input

The input is given in the following format.

$n \; q$
$query_1$
$query_2$
:
$query_q$

Each query $query_i$ is given by

0 $t$ $x$

or

1 $t$

or

2 $s$ $t$

where the first digits 0, 1 and 2 represent insert, dump and splice operations respectively.

Output

For each dump operation, print elements of the corresponding list in a line. Separete adjacency elements by a space character (do not print the space after the last element). Note that, if the list is empty, an empty line should be printed.

Constraints

$1 \leq n \leq 1,000$

$1 \leq q \leq 500,000$

For a splice operation, $s \ne t$

For a splice operation, $L_s$ is not empty

The total number of elements printed by dump operations do not exceed 1,000,000

$-1,000,000,000 \leq x \leq 1,000,000,000$

Sample Input 1

3 10
0 0 1
0 0 2
0 0 3
0 1 4
0 1 5
2 1 0
0 2 6
1 0
1 1
1 2

Sample Output 1

1 2 3 4 5

6

Solution in Go (judge verdict: Time Limit Exceeded)

package main

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

var scanner = bufio.NewScanner(os.Stdin)

func nextInt() int {
	scanner.Scan()
	i, e := strconv.Atoi(scanner.Text())
	if e != nil {
		panic(e)
	}
	return i
}

func main() {
	scanner.Split(bufio.ScanWords)
	n := nextInt()
	q := nextInt()
	A_slices := make([][]int, n)
	for i := 0; i < n; i++ {
		A_slices[i] = make([]int, 0)
	}
	for i := 0; i < q; i++ {
		// fmt.Println(A_slices)
		switch nextInt() {
		case 0:
			t := nextInt()
			x := nextInt()
			A_slices[t] = append(A_slices[t], x)
		case 1:
			t := nextInt()
			if len(A_slices[t]) == 0 {
				fmt.Println()
				continue
			}
			for i := 0; i < len(A_slices[t]); i++ {
				if i == len(A_slices[t])-1 {
					if len(A_slices[t])-1 == 1 {
						fmt.Printf("%d\n", A_slices[t][i])
					} else {
						fmt.Printf("%d\n", A_slices[t][i])
					}
				} else {
					fmt.Printf("%d ", A_slices[t][i])
				}
			}
		case 2:
			s := nextInt()
			t := nextInt()
			if len(A_slices[s]) == 0 {
				continue
			}
			A_slices[t] = append(A_slices[t], A_slices[s]...)
			A_slices[s] = make([]int, 0)
		default:
			panic("no such operation!")
		}
	}
}