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How to calculate the least common multiple (LCM) of two numbers in Python

How to calculate the least common multiple (LCM) of two numbers in Python.

Here is a step-by-step tutorial on how to calculate the least common multiple (LCM) of two numbers in Python:

Step 1: Understand the concept of Least Common Multiple (LCM)​

The LCM of two or more numbers is the smallest multiple that is divisible by all given numbers. In other words, it is the lowest common multiple of the given numbers.

Step 2: Take user input for two numbers​

To calculate the LCM, you need to take input from the user for the two numbers for which you want to find the LCM. You can use the input() function to take user input.

num1 = int(input("Enter the first number: "))
num2 = int(input("Enter the second number: "))

Step 3: Find the maximum of the two numbers​

To find the LCM, you need to start by finding the maximum of the two numbers. You can use the max() function to get the maximum value.

maximum = max(num1, num2)

Step 4: Write a function to calculate the LCM​

Now, you can write a function to calculate the LCM. There are different algorithms to find the LCM, but one common approach is to use the formula:

LCM = (num1 * num2) / GCD(num1, num2)

where GCD stands for Greatest Common Divisor. You can use the math module in Python to find the GCD. Here's an example implementation:

import math

def find_lcm(num1, num2):
    gcd = math.gcd(num1, num2)
    lcm = (num1 * num2) // gcd
    return lcm

Step 5: Call the function and display the result​

After defining the function, you can call it by passing the two input numbers as arguments. Finally, you can display the calculated LCM using the print() function.

lcm = find_lcm(num1, num2)
print("The LCM of", num1, "and", num2, "is", lcm)

Step 6: Run the program and test it​

Now you can run the program and test it with different input numbers to calculate the LCM.

Here's the complete code:

import math

def find_lcm(num1, num2):
    gcd = math.gcd(num1, num2)
    lcm = (num1 * num2) // gcd
    return lcm

num1 = int(input("Enter the first number: "))
num2 = int(input("Enter the second number: "))

lcm = find_lcm(num1, num2)
print("The LCM of", num1, "and", num2, "is", lcm)

That's it! You have successfully written a Python program to calculate the least common multiple (LCM) of two numbers.