#include <bits/stdc++.h>
using namespace std;
#define pb push_back
const int N=2e5+5,INF=1e9;
int T,n,n1,tp,ans,l[N],r[N],ds[N],o[N],o1[N],st[N],z[N][18];
int id(int x) {return upper_bound(ds+1,ds+n1+1,x)-ds-1;}
int get(int x,int y)
{
	int res=0;
	for(int i=17;i>=0;--i) if(z[x][i]>=y)
		x=z[x][i],res+=1<<i;return res;
}
bool chk(int x)
{
	tp=0;st[++tp]=0;
	for(int i=1,t;i<=n1;++i)
	{
		t=lower_bound(st+1,st+tp+1,o[i])-st;
		if(t>tp) return 0;z[i][0]=st[t];
		for(int j=1;j<=17;++j) z[i][j]=z[z[i][j-1]][j-1];
		if(get(i,o1[i])<x) st[++tp]=i;
	}return 1;
}
void slv()
{
	scanf("%d",&n);n1=ans=0;
	for(int i=1;i<=n;++i)
		scanf("%d %d",&l[i],&r[i]),ds[++n1]=l[i],ds[++n1]=r[i]+1;
	sort(ds+1,ds+n1+1);n1=unique(ds+1,ds+n1+1)-ds-1;
	fill(o,o+n1+1,0);fill(o1,o1+n1+1,INF);
	for(int i=1;i<=n;++i) l[i]=id(l[i]),r[i]=id(r[i]),
		o[r[i]+1]=max(o[r[i]+1],l[i]),o1[r[i]]=min(o1[r[i]],l[i]);
	for(int i=1;i<=n1;++i) o[i]=max(o[i],o[i-1]);
	for(int i=n1-1;i;--i) o1[i]=min(o1[i],o1[i+1]);
	for(int i=1;i<=n1;++i)
	{
		z[i][0]=o[i];
		for(int j=1;j<=17;++j) z[i][j]=z[z[i][j-1]][j-1];
	}for(int i=1;i<=n;++i) ans=max(ans,get(r[i]+1,l[i]));
	if(!chk(ans)) chk(++ans);
	tp=0;for(int i=z[n1][0];i;i=z[i][0]) st[++tp]=ds[i];
	printf("%d %d ",ans,tp);
	for(int i=tp;i;--i) printf("%d%c",st[i],i>1?' ':'\n');
}
int main()
{
	scanf("%d",&T);
	while(T--) slv();return 0;
}