### Re: 11388 - GCD LCM

Posted:

**Thu Oct 01, 2009 11:06 am**Another One of the easiest problem like Hasmot the brave warrior:

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

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