{
tree[u].l=l;
tree[u].r=r;
tree[u].flag=0;
if(l==r)return ;
int mid=(l+r)>>1;
build_tree(l,mid,LL(u));
build_tree(mid+1,r,RR(u));
}
void update(int l,int r,int u,int i)
{
if(l>tree[u].r||r
{
tree[u].flag=i;
return ;
}
if(tree[u].flag > 0 && tree[u].flag != i)
{
tree[LL(u)].flag = tree[u].flag;
tree[RR(u)].flag= tree[u].flag;
tree[u].flag = 0;
}
int mid=(tree[u].l+tree[u].r)>>1;
if(r<=mid)
update(l,r,LL(u),i);
else if(l>mid)
update(l,r,RR(u),i);
else
{
update(l,mid,LL(u),i);
update(mid+1,r,RR(u),i);
}
if(tree[LL(u)].flag==tree[RR(u)].flag)
tree[u].flag=tree[LL(u)].flag;
else
tree[u].flag=0;
}
int ans;
int yinshe[20005];
int visit[10000005];
bool visit1[20005];
void query(int l,int r,int u)
{
if(tree[u].flag&&!visit1[tree[u].flag])
return ;
if(tree[u].flag)
ans+=visit1[tree[u].flag];
visit1[tree[u].flag]=0;
return ;
}
int mid=(l+r)>>1;
query(l,mid,LL(u));
query(mid+1,r,RR(u));
}
int main()
{
int i,j,k,l,n,m,T;
scanf("%d",&T);
int a,b;
while(T--)
{
memset(visit1,1,sizeof(visit1));
memset(visit,0,sizeof(visit));
memset(yinshe,0,sizeof(yinshe));
scanf("%d",&n);
int num=1;
for(i=1; i<=n; i++)
{
scanf("%d%d",&aa[i],&bb[i]);
if(!visit[aa[i]])
{
yinshe[num]=aa[i];
visit[aa[i]]=1;
num++;
}
if(!visit[bb[i]])
{
yinshe[num]=bb[i];
visit[bb[i]]=1;
num++;
}
}
sort(yinshe+1,yinshe+num);
for(i=1; i
build_tree(1,num-1,1);
for(i=1;i<=n;i++)
update(visit[aa[i]],visit[bb[i]],1,i);
ans=0;
query(1,num-1,1);
printf("%d\n",ans);
}
return 0;
}