English
Zadanie Dzielniki (dzi)
Divisors
Memory limit: 128 MB
We are given a set 
of 
positive integers.
We would like to find a subset 
of 
, composed of as few elements as possible,
such that the only positive common divisor of all the elements of 
is 1.
Input
The first line of input contains one integer 
(
),
the size of the set 
.
The second line contains a sequence of 
positive integers 
(
) that represents the elements of the set 
.
Output
The only line of output should contain one integer: the size of the requested smallest
set 
or a single word BRAK (Polish for none) if the set does not exist.
Example
For the input data:
5 6 10 12 15 18
the correct result is:
3
whereas for the input data:
5 2 4 6 8 10
the correct result is:
BRAK
Task author: Jakub Lacki.