#include<bits/stdc++.h>
using namespace std;
int m,n,tot=0,T;
int v[200010],q[200010];//,jie[10010],ud[10010];
vector<int>p[200010],fp[200010];
int exx(int x){
	if(x<=n)return x+n;
	return x-n;
}
void ex(int x,int a,int y,int b){
	int w=x,z=y;
	if(a)x+=n;else w+=n;
	if(b)y+=n;else z+=n;
	p[w].push_back(y);
	p[z].push_back(x);
	fp[y].push_back(w);
	fp[x].push_back(z);
}
void dfs1(int x){
	v[x]=1;
	int i,j,k,l=fp[x].size();
	for(i=0;i<l;i++){
		k=fp[x][i];
		if(!v[k])dfs1(k);
	}
	q[++tot]=x;
}
int dfs2(int x,int y){
	v[x]=0;
	if(x==y)return 1;
	int i,j,k,l=p[x].size();
	for(i=0;i<l;i++){
		k=p[x][i];
		if(v[k])
			if(dfs2(k,y))return 1;
	}
	return 0;
}
int main(){
	cin>>T;
	while(T--){
		cin>>n>>m;
		int i,j,k,fl=0,x,y,a,b;tot=0;
		memset(v,0,sizeof v);
		memset(q,0,sizeof q);
		for(i=0;i<=n;i++)p[i].clear(),fp[i].clear();
		
		string s1,s2;
		while(m--){
			cin>>s1>>s2;
			if(s1[0]=='m')a=0;else a=1;
			if(s2[0]=='m')b=0;else b=1;
			x=0;for(i=1;i<s1.size();i++)x=x*10+s1[i]-'0';
			y=0;for(i=1;i<s2.size();i++)y=y*10+s2[i]-'0';
	//		printf("(%d %d %d %d)\n",x,a,y,b);
			ex(x,a,y,b);
		}
		for(i=1;i<=n*2;i++){
			if(!v[i])dfs1(i);
		}
		while(tot){
			if(v[q[tot]])
				if(dfs2(q[tot],exx(q[tot]))){
					cout<<"BAD"<<endl,fl=1;break;
				}
			tot--;
		}
		if(!fl){
			cout<<"GOOD"<<endl;
		}
	}
	return 0;
}