#include <bits/stdc++.h>
#define N 200011
#define pii pair<int,int>
#define s1 first
#define s2 second
using namespace std;
vector<int> vv;int t,n,l[N],r[N];
int ID(int x){return lower_bound(vv.begin(),vv.end(),x)-vv.begin();}
int to[N][21],dis[N],X;
bool vis[N];
vector<pii> G[N];
int F(int w){return w==1?X:w;}
vector<int> vl[N],vr[N];
int tor[N],tolx[N];
bool spfa()
{
	for(int i=0;i<vv.size();++i)dis[i]=0;
	for(int i=vv.size()-1;~i;--i)
	{
		if(i)dis[i-1]=min(dis[i],dis[i-1]);
		if(~tor[i])dis[tor[i]]=min(dis[tor[i]],dis[i]-1);
	}
	for(int i=0;i<vv.size();++i)vis[i]=0;
	static queue<int> q;int cc=0;
	while(!q.empty())q.pop();
	for(int i=0;i<vv.size();++i)q.push(i),vis[i]=1;
	while(!q.empty())
	{
		int p=q.front();q.pop();++cc;vis[p]=0;
		if(cc>2*vv.size())return 0;
		for(auto [v,w]:G[p])if(dis[v]>dis[p]+F(w))
		{
			dis[v]=dis[p]+F(w);
			if(!vis[v])q.push(v),vis[v]=1;
		}
	}
	return 1;
}
int getx(int l,int r)
{
	int ans=0;
	for(int i=17;~i;--i)if(to[r][i]>=l)r=to[r][i],ans+=1<<i;
	return ans;
}
int main()
{
	scanf("%d",&t);while(t--)
	{
		scanf("%d",&n);vv.clear();
		for(int i=1;i<=n;++i)
		{
			scanf("%d%d",l+i,r+i);
			vv.push_back(l[i]-1);
			vv.push_back(r[i]);
		}
		sort(vv.begin(),vv.end());vv.resize(unique(vv.begin(),vv.end())-vv.begin());
		for(int i=0;i<vv.size();++i)tor[i]=tolx[i]=-1;
		for(int i=1;i<=n;++i)
		{
			l[i]=ID(l[i]-1);r[i]=ID(r[i]);
			tor[r[i]]=max(tor[r[i]],l[i]);
			tolx[l[i]]=max(tolx[l[i]],r[i]);
		}
		for(int i=0;i<vv.size();++i)G[i].clear();
		for(int i=0;i<vv.size();++i)to[i][0]=-1;
		for(int i=0;i<vv.size();++i)
		{
			if(~tor[i])
			{
				G[i].push_back({tor[i],-1});
				to[i][0]=max(to[i][0],tor[i]);
			}
			if(i)to[i][0]=max(to[i][0],to[i-1][0]);
			if(~tolx[i])G[i].push_back({tolx[i],1});
			if(i)G[i].push_back({i-1,0});
		}
		for(int i=0;i<vv.size();++i)for(int j=1;j<=17;++j)
		{
			if(!~to[i][j-1])to[i][j]=-1;
			else to[i][j]=to[to[i][j-1]][j-1];
		}
		X=0;
		for(int i=1;i<=n;++i)X=max(X,getx(l[i],r[i]));
		if(!spfa())++X,spfa();
		printf("%d ",X);
		printf("%d ",-dis[0]);
		for(int i=1;i<vv.size();++i)if(dis[i]!=dis[i-1])printf("%d ",vv[i]);putchar(10);
	}
}