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import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.io.StreamTokenizer;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.PriorityQueue;
import java.util.Queue;
import java.util.Scanner;
import java.util.Stack;
import java.util.StringTokenizer;

import com.sun.org.apache.regexp.internal.recompile;

import sun.security.krb5.Asn1Exception;

public class Main {

public static void main(String[] args) throws IOException{
StreamTokenizer cin = new StreamTokenizer(new BufferedInputStream(System.in));
InputReader in = new InputReader(System.in)  ;
PrintWriter out = new PrintWriter(System.out) ;

int t = in.nextInt() ;
while(t-- > 0){
new Task().solve(in , out)  ;
}
out.flush() ;
}

}

class Task{

int m  , n  , sum ;
static  int[]u = new int[30]  ;
static  int[]v = new int[30]  ;
static  int[] du = new int[10]  ;
static  int[] on = new int[10] ;
static  int[] off = new int[10] ;

void dfs(int id){
if(id == m+1){
for(int i = 1 ; i <= n ; i++){
if(on[i] != off[i]) return ;
}
sum++ ;
return ;
}

int x = u[id]   ;
int y = v[id]   ;

if(on[x] < du[x] && on[y] < du[y]){
on[x]++ ;
on[y]++ ;
dfs(id + 1) ;
on[x]-- ;
on[y]-- ;
}

if(off[x] < du[x] && off[y] < du[y]){
off[x]++ ;
off[y]++ ;
dfs(id + 1) ;
off[x]-- ;
off[y]-- ;
}

}

public void solve(InputReader in , PrintWriter out) throws IOException{

n = in.nextInt() ;
m = in.nextInt() ;

Arrays.fill(du, 0) ;
for(int i = 1 ; i <= m ; i++){
u[i] = in.nextInt() ;
v[i] = in.nextInt() ;
du[u[i]]++ ;
du[v[i]]++ ;
}

for(int i = 1 ; i <= n ; i++){
if((du[i] & 1) == 1){
out.println(0) ;
return ;
}
du[i] >>= 1 ;
}

sum = 0 ;
Arrays.fill(on, 0)  ;
Arrays.fill(off, 0) ;
dfs(1) ;
out.println(sum) ;
//  out.flush() ;
}

}

class InputReader{
public BufferedReader reader;
public StringTokenizer tokenizer;

public InputReader(InputStream stream){
reader = new BufferedReader(new InputStreamReader(stream), 32768);
tokenizer = null;
}

public String next(){
while(tokenizer == null || !tokenizer.hasMoreTokens()){
try{
tokenizer = new StringTokenizer(reader.readLine());
}catch (IOException e) {
throw new RuntimeException(e);
}
}
return tokenizer.nextToken();
}

public int nextInt() {
return Integer.parseInt(next());
}

public long nextLong() {
return Long.parseLong(next());
}

}