#include <iostream>
#include <vector>
#include <algorithm>
#include <cstring>
using namespace std;

bool Pairing [10][10];
bool Taken [10];
int Pair_number;
int Student_number=0;
//매칭함수
int matching (bool Taken [10])
{
    int First_student =0;
    bool finished = true ;
    for(int a =0; a<Student_number; ++a)
    {
     if(Taken[a]==0)
     { First_student =a;
         finished = false ;
     break;}
    }
     if(finished == true)
     {return 1;}
//기저완료
    int Pairing_number =0;
    for(int Second_student = First_student+1; Second_student < Student_number; ++Second_student)
    {
        if((Taken[Second_student]==0) && (Taken[First_student]==0) && (Pairing[First_student][Second_student]==1))
        {
        Taken[Second_student]=1;
        Taken[First_student]=1; 
        Pairing_number += matching(Taken);
        Taken[Second_student]=0;
        Taken[First_student]=0; 
        }
    }
    return Pairing_number;
}

//메인함수

int main ()
{   
    memset(Pairing,0,sizeof(Pairing));
    memset(Taken,0,sizeof(Taken));
    int C,i,j;
    cin>>C;
    while(C--)
    {
        cin>>Student_number>>Pair_number;
        while(Pair_number--)
        {cin>>i>>j;
        Pairing[i][j]=1;
        Pairing[j][i]=1;
        }
        //함수
        cout<<matching(Taken)<<endl;
    }
 return 0;
}

}