#include<bits/stdc++.h>
using namespace std;

const int N=205;
int t,n,m;
int head[N],idx;
struct Edge{int to,ne;}e[4005];
int dfn[N],low[N],tim,stk[N],top,scc[N],cnt;
char s1[5],s2[5];
 
void add(int a,int b){
  e[++idx].to=b;
  e[idx].ne=head[a];
  head[a]=idx;
}
void tarjan(int x){
  dfn[x]=low[x]=++tim;
  stk[++top]=x;
  for(int i=head[x];i;i=e[i].ne){
    int y=e[i].to;
    if(!dfn[y]){ //若y尚未访问
      tarjan(y);
      low[x]=min(low[x],low[y]);
    }
    else if(!scc[y]) //若y已访问且未处理
      low[x]=min(low[x],dfn[y]);
  }
  
  if(low[x]==dfn[x]){ //若x是SCC的根
    ++cnt;
    for(int y=-1;y!=x;) scc[y=stk[top--]]=cnt;
  }
}
int main(){
  scanf("%d",&t);
  while(t--){
    idx=tim=cnt=top=0;
    memset(head,0,sizeof head);
    memset(dfn,0,sizeof dfn);    
    memset(scc,0,sizeof scc);
    scanf("%d%d",&n,&m);
    while(m--){
      scanf("%s%s",&s1,&s2);
      int i=0,j=0,a,b,k;
      a=(s1[0]=='m'?0:1);
      b=(s2[0]=='m'?0:1);
      for(k=1;s1[k]>='0'&&s1[k]<='9';)
        i=i*10+s1[k++]-'0';
      for(k=1;s2[k]>='0'&&s2[k]<='9';)
        j=j*10+s2[k++]-'0';
      add(i+n*!a,j+n*b); 
      add(j+n*!b,i+n*a);
    }
    
    for(int i=1;i<=n<<1;++i)if(!dfn[i])tarjan(i);
    bool flag=0;
    for(int i=1;i<=n;++i)
      if(scc[i]==scc[i+n]){
        flag=1; break;
      }
    flag?puts("BAD"):puts("GOOD");
  }
}