package algorithm;

import java.util.*;

public class GraphListList {

static int N;

static List<Integer>[] g;

static boolean[] v;

public static void main(String[] args) {

Scanner sc = new Scanner(System.in);

N = sc.nextInt();

int E = sc.nextInt();

g = new List[N];

for (int i = 0; i < N; i++)

g[i] = new ArrayList<>();

v = new boolean[N];

for (int i = 0; i < E; i++) {

int from = sc.nextInt();

int toto = sc.nextInt();

g[from].add(toto);

g[toto].add(from);

}

for (List<Integer> a : g)

System.out.println(a);

System.out.println();

bfs(0);

// dfs(0);

sc.close();

}

static void bfs(int i) {

ArrayDeque<Integer> q = new ArrayDeque<>();

v[i] = true;

q.offer(i);

while (!q.isEmpty()) {

i = q.poll();

System.out.print((char) (i + 'A') + " ");

for (int j : g[i]) {

if (!v[j]) {

v[j] = true;

q.offer(j);

}

}

}

}

static void dfs(int i) {

v[i] = true;

System.out.print((char) (i + 'A') + " ");

for (int j : g[i]) {

if (!v[j])

dfs(j);

}

}

}

/*

* 7

* 8

* 0 1

* 0 2

* 1 3

* 1 4

* 2 4

* 3 5

* 4 5

* 5 6

*

* A0

* / \

* B1 C2

* / \ /

* D3 E4

* \ /

* F5 - G6

*/