#include<stdio.h>
#include<string.h>

FILE *f=fopen("zvon.in","r"),*g=fopen("zvon.out","w");
long a[100002],niv,n,t,s;
char v[100002];
void re()
{
fscanf(f,"%d",&n);
long x,y;
for(long i=1;i<n;i++)
  {fscanf(f,"%d%d",&x,&y);
  a[y]=x;
  }
}

void st(long j,long k)
{
v[j]=1;
if(niv<=k) {niv=k; s=a[j]; }
for(int i=1;i<=n;i++)
   if(a[i]==j&&v[i]==0)
      st(i,k+1);
}


void go()
{
fscanf(f,"%d",&t);
for(long i=1;i<=t;i++)
   {
   memset(v,0,sizeof(v));
   niv=0;
   re();
   long j=1;
   while(a[j]!=0) j++;
   st(j,0);
   for(long j=1;j<=n;j++)
      if(s==a[j]) niv++;
   fprintf(g,"%d\n",niv-1);
   }
}




int main()
{
go();
return 0;
}