/* 
 * Merger the segments, and break them into Monotone Chains
 */

import java.util.*;
import java.io.*;

public class Merge {
	HashMap hm=new HashMap();
    String prelog;
    private String infile,outfile;
    Vector vChain=new Vector();
    
    public Merge(String s1,String s2){
        infile=s1;
        outfile=s2;
    }
    
    public void process() {
	    try{
	        InputStream in=new FileInputStream(infile);
	        BufferedReader ins= new BufferedReader(new InputStreamReader(in));
	        prelog=ins.readLine()+"\n"+ins.readLine()+"\n"+ins.readLine()+"\n"+ins.readLine()+"\n";
	        String s;
	        while((s=ins.readLine())!=null){
	        	Chain c=new Chain();	
	        	for(int k=0;k<s.length();k+=19)
	        	    c.addPoint(s.substring(k+1,k+19));
	        	vChain.add(c);
	        }
	        merge();
	        breakToMonotone();
	        OutputStreamWriter outs= new OutputStreamWriter(new FileOutputStream(outfile));
			outs.write(prelog);
			for(int i=0;i<vChain.size(); i++){
				outs.write((Chain)vChain.get(i)+"\n");
			}
			outs.flush();
			outs.close();
	    }catch(IOException e){System.out.println(e);}
    }

	public void merge() {
		System.out.println("Number of chains before merging:"+vChain.size());
		for(int i=0;i<vChain.size();i++){
			Chain c=(Chain)vChain.get(i);
			countDegree(c.first());
			countDegree(c.last());
		}
		
		for(int i=0;i<vChain.size();i++){
			Chain c=(Chain)vChain.get(i);
			boolean changed=true;
			while(changed){
				changed = false;
				Chain c2=null;
				if (getDegree(c.first())==2){
					for(int j=i+1;j<vChain.size();j++){
						c2=(Chain)vChain.get(j);
						if((c2.first().equals(c.first()))||(c2.last().equals(c.first()))){
							c.merge(c2);
							vChain.remove(c2);changed=true;	
							break;
						}
					}
				}else if (getDegree(c.last())==2){
					for(int j=i+1;j<vChain.size();j++){
						c2=(Chain)vChain.get(j);
						if((c2.first().equals(c.last()))||(c2.last().equals(c.last()))){
							c.merge(c2);
							vChain.remove(c2);changed=true;	
							break;
						}
					}
				}
			}
			vChain.set(i,c);	
		}
		System.out.println("Number of chains after merging:"+vChain.size());
	}
	
	public void breakToMonotone(){
		Vector tempv=new Vector();
		for(int i=0;i<vChain.size();i++){
			Chain c=(Chain)vChain.get(i);
			tempv.addAll(c.getXMonoSet());
		}
		vChain=tempv;
		System.out.println("Number of chains after breaking to monotone chains:"+vChain.size());
		return;
	}
	
	public void countDegree(String s){
		if (hm.get(s)==null)
			hm.put(s,new Integer(1));
		else
			hm.put(s,new Integer(((Integer)hm.get(s)).intValue()+1));
		return;
	}
	
		
	public int getDegree(String s){
		return ((Integer)hm.get(s)).intValue();
	}
	
	
    public static void main(String s[]) {
        if(s.length!=2){
                        System.out.println("Usage : java Merge inputFilename outputFilenam");
                        System.exit(-1);
                }
                
        Merge m = new Merge(s[0],s[1]);
        m.process();
    }

}

class Chain {
	Vector v=new Vector();
	void addPoint(String s){
		v.add(s);
	}
	public String toString(){
		String s="";
		for(int i=0;i<v.size();i++){
			s+=" "+(String)v.get(i);
		}
		return s;
	}
	String first(){
		return (String)v.firstElement() ;
	}
	String last(){
		return (String)v.lastElement() ;
	}
	Vector getV(){
		return v;
	}
	void merge(Chain c2){
		Vector v2=c2.getV();
		if(first().equals(c2.first()))
			for(int i=1;i<v2.size();i++)v.insertElementAt(v2.get(i),0);
		else if(first().equals(c2.last()))
			for(int i=v2.size()-2;i>=0;i--)v.insertElementAt(v2.get(i),0);
		else if(last().equals(c2.first()))
			for(int i=1;i<v2.size();i++)v.add(v2.get(i));
		else if(last().equals(c2.last()))
			for(int i=v2.size()-2;i>=0;i--)v.add(v2.get(i));
	}
	Vector getXMonoSet(){
		Vector newv=new Vector();
		Chain c=new Chain();
		c.addPoint((String)v.get(0));c.addPoint((String)v.get(1));
		for(int i=2;i<v.size();i++){
			if(SameDirection((String)v.get(i-2),(String)v.get(i-1),(String)v.get(i))){
				c.addPoint((String)v.get(i));
			}else{
				newv.add(c);
				c=new Chain();
				c.addPoint((String)v.get(i-1));c.addPoint((String)v.get(i));
			}
		}
		newv.add(c);
		return newv;
	}
	
	private boolean SameDirection(String p1,String p2,String p3){
		long x1=new Integer(p1.substring(0,9)).longValue();
		long x2=new Integer(p2.substring(0,9)).longValue();
		long x3=new Integer(p3.substring(0,9)).longValue();
		return(((x1<=x2)&&(x2<=x3))||((x1>=x2)&&(x2>=x3)));
	}	
}