rem Programming Contest Problem
rem Find the gcd of two numbers

rem Solution 2: use Euclid's algorithm

Input "First number: " a
Input "Second number: " b

20 if a = b then
     gcd = a
     goto 50
   else
     if a > b then
       a = mod(a,b)
       if a = 0 then
         gcd = b
         goto 50
       endif
     else
       b = mod(b,a)
       if b = 0 then
         gcd = a
         goto 50
       endif
     endif
 endif
goto 20

50 print "GCD: ", gcd
end