! ==== testkib.factor ====
! Copyright Kibleur Christophe - 2008
 
IN: testkib

! prettyprint for using "."
USING: prettyprint io math kernel ;

: pgcd ( a b -- c )
    2dup ! Stack is now : a b a b
    /i dup ! Stack is now : a b a b remainder
    ! Returns b if remainder=0, else call pgcd on last two elements
    0 = [ drop swap drop ] [ drop swap pgcd ] if . ;

10 4 pgcd