We consider a geographical map with N countries numbered from 1 to N (0 < N < 99). For every country we know the numbers of other countries which are connected with its border. From every country we can reach to any other one, eventually crossing some borders. Write a program which determines whether it is possible to color the map only in two colors — red and blue in such a way that if two countries are connected their colors are different. The color of the first country is red. Your program must output one possible coloring for the other countries, or show, that such coloring is impossible.
Input
On the first line is written the number N. On the following N lines, the ith line contains the countries to which the ith country is connected. Every integer on this line is bigger than i, except the last one which is 0 and marks that no more countries are listed for country i. If a line contains 0, that means that the ith country is not connected to any other country, which number is larger than i.
Output
The output contains exactly one line. If the coloring is
possible, this line must contain a list of zeros and ones,
without any separators between them. The ith digit
in this sequence is the color of the ith country. 0 corresponds to red color, and one — to blue color. If a coloring is not possible, output the integer −1.
Sample
input  output 

3
2 0
3 0
0
 010

Problem Author: Emil Kelevedzhiev
Problem Source: Winter Mathematical Festival Varna '2001 Informatics Tournament