Problem Statement

Find the greatest common divisor   (GCD)   of two integers.

Greatest common divisor   is also known as   greatest common factor (gcf)   and   greatest common measure.

Let's start with the solution:

::
:: Greatest common divisor (gcd), Euclid's algorithm.
::
|=  [a=@ud b=@ud]
^-  @ud
?>  (gth b 0)
?:  =((mod a b) 0)
  b
$(a b, b (mod a b))