11388 - GCD LCM

Difficulty : trivial

Solution Description :

Easy Problem

we know that 
a x b= gcd(a,b) x lcm(a,b)
or gcd(a,b) x lcm(a,b)= a x b ....................(1)

Input is : gcd(a,b) and lcm(a,b)
output : a=?, b=?
from equation (i)
there is symmetry

try:
from forward: a=12, b=18
gcd(12,18)=6, lcm(12,18)=36
12 x 18 = 6 x 36

from reverse: a=6, b=36
gcd(6,36)= 6, lcm(6,36)= 36
6 x 36 = 6 x 36

ha ha ha ............
just : input = output if b is divisible by a
otherwise print -1