Python Program to find l.c.m. of two numbers

In this tutorial, we are going to learn writing the python program to calculate the least common multiple of two numbers.

Problem Statement

For any two numbers given by the user as an input, we have to calculate and print the l.c.m. of that numbers using python programming language.

 For example:

Case1: If the user inputs the numbers 4 and 6.

             then the output should be ‘12’.

Case2: If the user inputs the numbers 5 and 7.

            then the output should be ‘35’.

Our logic to find l.c.m. of two numbers

• Our program will take 2 inputs of integers.
• Our program will calculate the l.c.m. of two numbers and return the calculated l.c.m. as the output of our program.

Python code to find l.c.m. of two numbers

num1 = int(input("Enter first number: "))  
num2 = int(input("Enter second number: "))  
if num1 > num2:  
    greater = num1  
else:  
    greater = num2  
while(True):  
    if((greater % num1 == 0) and (greater % num2 == 0)):  
        lcm = greater  
        break  
    greater += 1  
print("LCM of",num1,"and",num2,"=",greater)

Output 1:

Enter first number: 9
Enter second number: 18
LCM of 9 and 18 = 18

Explanation:

For inputs 9 and 18, we are dividing the ‘greater’ with both num1 and num2 to find the common multiple of 9 and 18. First greater assigned with value 18 and then in while loop it checking continuously that if ‘18/9 == 0 and 18/18 == 0’ which is true so the value of greater is returned as the L.C.M. of 9 and 18. 

Output 2:

Enter first number: 6
Enter second number: 24
LCM of 6 and 24 = 24

Explanation:

For inputs 6 and 24, we are dividing the ‘greater’ with both num1 and num2 to find the common multiple of 6 and 24. First greater assigned with value 24 and then in while loop it checking continuously that if ‘24/6 == 0 and 24/24 == 0’ which is true so the value of greater is returned as the L.C.M. of 24 and 6.