#include<iostream>

#include<cstdio>

#include<algorithm>

#include<cstring>

using namespace std;

typedef long long ll;

int de[10];

int in[100], out[100];

int on[10], off[10];

int ans, m, n;

void dfs( int u )

{

	if(u == m + 1)

	{

		for(int i = 1; i <= n; i++)

		{

			if(on[i] != off[i]) return;

		}

		ans++;

		return;

	}

	if(on[in[u]] < de[in[u]] / 2 && on[out[u]] < de[out[u]]/2)

	{

		on[in[u]]++; on[out[u]]++;

		dfs( u + 1 );

		on[in[u]]--; on[out[u]]--;

	}

	if(off[in[u]] < de[in[u]] / 2 && off[out[u]] < de[out[u]]/2)

	{

		off[in[u]]++; off[out[u]]++;

		dfs( u + 1 );

		off[in[u]]--; off[out[u]]--;

	}

}

int main()

{

	int kase;

	scanf( "%d", &kase );

	while(kase--)

	{

		memset( de, 0, sizeof de );

		memset( on, 0, sizeof on );

		memset( off, 0, sizeof off );

		ans = 0;

		scanf( "%d%d", &n, &m );

		for(int i = 1; i <= m; i++)

		{

			scanf( "%d%d", &in[i], &out[i] );

			de[in[i]]++; de[out[i]]++;

		}

		int flag = true;

		for(int i = 1; i <= n; i++)

		{

			if(de[i] % 2 == 1)

			{

				printf( "0\n" );

				flag = false;

				break;

			}

		}

		if(!flag) continue;

		dfs( 1 );

		printf( "%d\n", ans );

	}

	return 0;

}