Find the other number when LCM and HCF given

Given a number A and L.C.M and H.C.F. The task is to determine the other number B.

Examples: 

Input: A = 10, Lcm = 10, Hcf = 50.
Output: B = 50

Input: A = 5, Lcm = 25, Hcf = 4.
Output: B = 20

Formula:

A * B = LCM * HCF 
B = (LCM * HCF)/A
Example : A = 15, B = 12 
HCF = 3, LCM = 60 
We can see that 3 * 60 = 15 * 12.

How does this formula work? 
Since HCF divides both the numbers, let. 
A = HCF * x 
B = HCF * y
Note that x and y are not common factors, so LCM must include HCF, x and y. 
So we can conclude. 
LCM = HCF * x * y
So LCM * HCF = HCF * x * y * HCF which is equal to A * B

Below is the implementation of the above approach: 

B = 1

Time Complexity: O(1)
Auxiliary Space: O(1)