/*
矩陣樹定理：
無向圖的生成樹個數就等於這副圖的拉普拉斯矩陣的任意一個代數餘子式值。
*/
#include <bits/stdc++.h>

#define ed end()
#define bg begin()
#define mkp make_pair
#define pb push_back
#define v(T) vector<T>
#define all(x) x.bg,x.ed
#define newline puts("")
#define si(x) ((int)x.size())
#define rep(i,n) for(int i=1;i<=n;++i)
#define rrep(i,n) for(int i=0;i<n;++i)
#define srep(i,s,t) for(int i=s;i<=t;++i)

using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
const int maxn = 50;
const int inf = 0x7f7f7f7f;
const ll inf_ll = 1ll*inf*inf;
const int Mod = 1e9+7;
const double eps = 1e-7;
int n,m;
int g[maxn][maxn];
ll L[maxn][maxn];

ll det(int n){
    ll ret = 1;
    for (int i=2;i<=n;i++){
        for (int j=i+1;j<=n;j++){
            while(L[j][i]){
                ll tmp=L[i][i]/L[j][i];//不存在除不盡的情況
                for(int k=i;k<=n;k++)
                    L[i][k] -= tmp*L[j][k];
                
                for(int k=i;k<=n;k++)
                    swap(L[i][k],L[j][k]);
                
                ret = -ret;
            }
        }
        if(!L[i][i]) return 0;
        ret *= L[i][i];
    }
    if(ret < 0) ret = -ret;
    return ret;
}
int main(){
    int T;
    scanf("%d",&T);
    for(int _=1;_<=T;_++)
    {
        memset(g,0,sizeof(g));
        memset(L,0,sizeof(L));
        scanf("%d%d",&n,&m);
        rep(i,m){
            int u,v;
            scanf("%d%d",&u,&v);
            g[u][v]=g[v][u]=1;
        }
        for (int i=1;i<=n;i++){
            for (int j=i;j<=n;j++){
                if(g[i][j]){
                    L[i][i]++;L[j][j]++;
                    L[i][j]--;L[j][i]--;
                }
            }
        }
        ll ans = det(n);
        printf("%lld\n",ans);
    }
    return 0;
}