Problem: You are given an undirected unweighted connected graph consisting of n vertices and m edges. It is guaranteed that there are no self-loops or multiple edges in the given graph.

Your task is to choose at most ⌊n/2⌋ vertices in this graph so each unchosen vertex is adjacent (in other words, connected by an edge) to at least one of chosen vertices.

It is guaranteed that the answer exists. If there are multiple answers, you can print any.

You will be given multiple independent queries to answer.

Input

The first line contains a single integer t (1 ≤ t ≤ 2 ⋅ 10^5) — the number of queries.

Then t queries follow.

The first line of each query contains two integers n and m (2 ≤ n ≤ 2 ⋅ 10^5, n - 1 ≤ m ≤ min(2 ⋅ 10^5, (n(n-1))/(2))) — the number of vertices and the number of edges, respectively.

The following m lines denote edges: edge i is represented by a pair of integers v_i, u_i (1 ≤ v_i, u_i ≤ n, u_i ≠ v_i), which are the indices of vertices connected by the edge.

There are no self-loops or multiple edges in the given graph, i. e. for each pair (v_i, u_i) there are no other pairs (v_i, u_i) or (u_i, v_i) in the list of edges, and for each pair (v_i, u_i) the condition v_i ≠ u_i is satisfied. It is guaranteed that the given graph is connected.

It is guaranteed that ∑ m ≤ 2 ⋅ 10^5 over all queries.

Output

For each query print two lines.

In the first line print k (1 ≤ ⌊n/2⌋) — the number of chosen vertices.

In the second line print k distinct integers c_1, c_2, ..., c_k in any order, where c_i is the index of the i-th chosen vertex.

It is guaranteed that the answer exists. If there are multiple answers, you can print any.

Example

Input


2
4 6
1 2
1 3
1 4
2 3
2 4
3 4
6 8
2 5
5 4
4 3
4 1
1 3
2 3
2 6
5 6


Output


2
1 3
3
4 3 6

Note

In the first query any vertex or any pair of vertices will suffice.

<image>

Note that you don't have to minimize the number of chosen vertices. In the second query two vertices can be enough (vertices 2 and 4) but three is also ok.

<image>

Solution (in JAVA):

Solution:

import java.io.*;
import java.io.IOException;
import java.util.*;

//import sun.net.www.content.audio.wav;

import java.text.DecimalFormat;
 
public class Codeforces {
	
	public static long mod = (long)Math.pow(10, 9)+7 ;
	public static double epsilon=0.00000000008854;//value of epsilon
	public static InputReader sc = new InputReader(System.in);
	public static PrintWriter pw = new PrintWriter(System.out);
	
	public static long gcd(long a,long b){
		while(b>0){
			long t=b;
			b=a%b;
			a=t;
		}
		return a;
	}
	public static int firstNode(int a,int p[]){
		if(a!=p[a]){
			p[a]=firstNode(p[a], p);
		}
		return p[a];
	}
	public static void Union(int a,int b,int p[]){
		//int a=firstNode(a1, p);
		//int b=firstNode(b1, p);
		/*if(a!=b){
			if(r[a]<r[b]){
				p[a]=b;
			}
			else if(r[a]>r[b]){
				p[b]=a;
			}
			else{
				r[b]++;
				p[a]=b;
			}
		}*/
		//if(a!=b)
		p[firstNode(a,p)]=firstNode(b,p);//if no rank than 
	}
	public static int countSet(int a){
		int c=0;
		while(a>0){
			a&=(a-1);
			c++;
		}
		return c;
	}

	public static int dis(int i,int d[],int p[]){
		if(d[i]!=0){
			return d[i];
		}
		else if(p[i]==-1){
			return d[i]=1;
		}
		else return d[i]=1+dis(p[i], d, p);
	}

	
       

	public static void main(String[] args) {
		// code starts..
		int q=sc.nextInt();
		while(q-->0){
			int n=sc.nextInt();
			int m=sc.nextInt();
			ArrayList<ArrayList<Integer>> a=new ArrayList<>();
			for(int i=0;i<n;i++){
				a.add(new ArrayList<>());
			}
			while(m-->0){
				int v=sc.nextInt()-1;
				int u=sc.nextInt()-1;
				a.get(v).add(u);
				a.get(u).add(v);
			}
			Deque<Integer> q1=new LinkedList<>();
			Deque<Integer> q2=new LinkedList<>();
			int vis[]=new int[n];
			for(int i=0;i<n;i++){
				if(vis[i]>0){
					continue;
				}
				Deque<Integer> bf=new LinkedList<>();
				bf.add(i);int k=0;
				while(bf.size()>0){
					int l=bf.size();					
					while(l-->0){	
						int v=bf.remove();
						//pw.print(v+" ");
						if(vis[v]==1)
						continue;
						vis[v]=1;
						if(k==0)
						q1.add(v+1);
						else q2.add(v+1);
						for(int j=0;j<a.get(v).size();j++){
							int u=a.get(v).get(j);
							if(vis[u]==0){
								bf.add(u);
							}
						}
					}
					//pw.print("\n");
					k^=1;
				}
			}
			if(q1.size()<=q2.size()){
				pw.println(q1.size());
				while(q1.size()>0){
					pw.print(q1.remove()+" ");
				}
				pw.print("\n");
			}
			else{
				pw.println(q2.size());
				while(q2.size()>0){
					pw.print(q2.remove()+" ");
				}
				pw.print("\n");
			}
		}
		// Code ends...
		pw.flush();
		pw.close();
	}
	static class tripletL implements Comparable<tripletL> {
		Long x, y, z;
 
		tripletL(long x, long y, long z) {
			this.x = x;
			this.y = y;
			this.z = z;
		}
 
		public int compareTo(tripletL o) {
			int result = x.compareTo(o.x);
			if (result == 0)
				result = y.compareTo(o.y);
			if (result == 0)
				result = z.compareTo(o.z);
 
			return result;
		}
 
		public boolean equlas(Object o) {
			if (o instanceof tripletL) {
				tripletL p = (tripletL) o;
				return (x - p.x == 0) && (y - p.y ==0 ) && (z - p.z == 0);
			}
			return false;
		}
 
		public String toString() {
			return x + " " + y + " " + z;
		}
 
		public int hashCode() {
			return new Long(x).hashCode() * 31 + new Long(y).hashCode() + new Long(z).hashCode();
		}
	}
	public static String Doubleformate(double a,int n){
		String s="";
		while(n-->0){
			s+='0';
		}
		DecimalFormat f =new DecimalFormat("#0."+s);
		return f.format(a);
	}
 
	public static Comparator<Integer[]> column(int i){
		return 
		new Comparator<Integer[]>() {
			@Override
			public int compare(Integer[] o1, Integer[] o2) {
				return o1[i].compareTo(o2[i]);//for ascending
				//return o2[i].compareTo(o1[i]);//for descending
			}
		};
	}
	public static Comparator<Integer[]> pair(){
		return 
		new Comparator<Integer[]>() {
			@Override
			public int compare(Integer[] o1, Integer[] o2) {
				int result=o1[0].compareTo(o2[0]);
				if(result==0)
				result=o1[1].compareTo(o2[1]);
				return result;
			}
		};
	}
	public static Comparator<Integer[]> Triplet(){
		return 
		new Comparator<Integer[]>() {
			@Override
			public int compare(Integer[] o1, Integer[] o2) {
			
					for(int i=0;i<3;i++){
						for(int j=i+1;j<3;j++){
							for(int k=0;k<3;k++){
								for(int p=k+1;p<3;p++){
									if((o1[i]==o2[k]&&o1[j]==o2[p])||(o1[j]==o2[k]&&o1[i]==o2[p])){
 
									}
								}
							}
						}
					}
					int result=o1[0].compareTo(o2[0]);
					if(result==0)
					result=o1[1].compareTo(o2[1]);
					if(result==0)
					result=o1[2].compareTo(o2[2]);
					return result;
			}
		};
	}
	
	
	public static String reverseString(String s){
		StringBuilder input1 = new StringBuilder(); 
        input1.append(s);  
		input1 = input1.reverse();
		return input1.toString();
	}
	public static int[] scanArray(int n){
		int a[]=new int [n];
		for(int i=0;i<n;i++)
		a[i]=sc.nextInt();
 
		return a;
	}
	public static long[] scanLongArray(int n){
		long a[]=new long [n];
		for(int i=0;i<n;i++)
		a[i]=sc.nextLong();
 
		return a;
	}
	public static String [] scanStrings(int n){
		String a[]=new String [n];
		for(int i=0;i<n;i++)
		a[i]=sc.nextLine();
 
		return a;
	}
	static class InputReader {
 
		private final InputStream stream;
		private final byte[] buf = new byte[8192];
		private int curChar, snumChars;
		private SpaceCharFilter filter;
 
		public InputReader(InputStream stream) {
			this.stream = stream;
		}
 
		public int snext() {
			if (snumChars == -1)
				throw new InputMismatchException();
			if (curChar >= snumChars) {
				curChar = 0;
				try {
					snumChars = stream.read(buf);
				} catch (IOException e) {
					throw new InputMismatchException();
				}
				if (snumChars <= 0)
					return -1;
			}
			return buf[curChar++];
		}
 
		public int nextInt() {
			int c = snext();
			while (isSpaceChar(c)) {
				c = snext();
			}
			int sgn = 1;
			if (c == '-') {
				sgn = -1;
				c = snext();
			}
			int res = 0;
			do {
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				res *= 10;
				res += c - '0';
				c = snext();
			} while (!isSpaceChar(c));
			return res * sgn;
		}
 
		public long nextLong() {
			int c = snext();
			while (isSpaceChar(c)) {
				c = snext();
			}
			int sgn = 1;
			if (c == '-') {
				sgn = -1;
				c = snext();
			}
			long res = 0;
			do {
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				res *= 10;
				res += c - '0';
				c = snext();
			} while (!isSpaceChar(c));
			return res * sgn;
		}
 
		public int[] nextIntArray(int n) {
			int a[] = new int[n];
			for (int i = 0; i < n; i++) {
				a[i] = nextInt();
			}
			return a;
		}
 
		public String readString() {
			int c = snext();
			while (isSpaceChar(c)) {
				c = snext();
			}
			StringBuilder res = new StringBuilder();
			do {
				res.appendCodePoint(c);
				c = snext();
			} while (!isSpaceChar(c));
			return res.toString();
		}
 
		public String nextLine() {
			int c = snext();
			while (isSpaceChar(c))
				c = snext();
			StringBuilder res = new StringBuilder();
			do {
				res.appendCodePoint(c);
				c = snext();
			} while (!isEndOfLine(c));
			return res.toString();
		}
 
		public boolean isSpaceChar(int c) {
			if (filter != null)
				return filter.isSpaceChar(c);
			return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
		}
 
		private boolean isEndOfLine(int c) {
			return c == '\n' || c == '\r' || c == -1;
		}
 
		public interface SpaceCharFilter {
			public boolean isSpaceChar(int ch);
		}
	}
 
}

class Bit{//1...n
	int a[];
	Bit(int n){
		a=new int[n+1];
	}
	void update(int i,int delta){
		while(i<a.length){
			a[i]+=delta;
			i+=i&(-i);
		}
	}
	int query(int i){
		int sum=0;
		while(i>0){
			sum+=a[i];
			i-=i&(-i);
		}
		return sum;
	}
}
class Point{
	int e,w;
	Point(int e,int w){
		this.e=e;
		this.w=w;
	}
}