Problem: Let's define a string <x> as an opening tag, where x is any small letter of the Latin alphabet. Each opening tag matches a closing tag of the type </x>, where x is the same letter.

Tegs can be nested into each other: in this case one opening and closing tag pair is located inside another pair.

Let's define the notion of a XML-text: 

  * an empty string is a XML-text
  * if s is a XML-text, then s'=<a>+s+</a> also is a XML-text, where a is any small Latin letter 
  * if s1, s2 are XML-texts, then s1+s2 also is a XML-text



You are given a XML-text (it is guaranteed that the text is valid), your task is to print in the following form: 

  * each tag (opening and closing) is located on a single line 
  * print before the tag 2 * h spaces, where h is the level of the tag's nestedness. 

Input

The input data consists on the only non-empty string — the XML-text, its length does not exceed 1000 characters. It is guaranteed that the text is valid. The text contains no spaces.

Output

Print the given XML-text according to the above-given rules.

Examples

Input

&lt;a&gt;&lt;b&gt;&lt;c&gt;&lt;/c&gt;&lt;/b&gt;&lt;/a&gt;


Output

&lt;a&gt;
  &lt;b&gt;
    &lt;c&gt;
    &lt;/c&gt;
  &lt;/b&gt;
&lt;/a&gt;


Input

&lt;a&gt;&lt;b&gt;&lt;/b&gt;&lt;d&gt;&lt;c&gt;&lt;/c&gt;&lt;/d&gt;&lt;/a&gt;


Output

&lt;a&gt;
  &lt;b&gt;
  &lt;/b&gt;
  &lt;d&gt;
    &lt;c&gt;
    &lt;/c&gt;
  &lt;/d&gt;
&lt;/a&gt;

Solution (in JAVA):

Solution:
import java.io.*;

public class xml1
{
public static void main(String args[])
{
int i,j,b=0,k=1,count=0,m=0;
String n;
char[] s=new char[1000];
try
{
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
n=br.readLine();
for(i=0;i<n.length();i++)
{
if(((n.charAt(i)>='a')&&(n.charAt(i)<='z'))||n.charAt(i)=='/')
{
s[b]=n.charAt(i);
b++;
}
}
for(i=0;i<b;i++)
{
if(s[i]=='/')
{
if(m==1)
m=0;
count--;
k=0;
}
else
{
for(j=0;j<2*count;j++)
System.out.print(" ");
if(k==1)
{
System.out.print("<"+s[i]+">"+"\n");
count++;
}
else
{
System.out.print("</"+s[i]+">"+"\n");
m=1;
k=1;
}
}
}
}
catch(Exception e)
{
System.out.println(e);
}
}
}