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C# - Find the Least Common Multiple (LCM) of Two Numbers

Here, we are going to learn how to find the Least Common Multiple of two numbers in C#? By Nidhi Last updated : April 15, 2023

Here we will find the LCM of two numbers. The LCM is the smallest number, which is the multiple of both numbers.

C# program to find the Least Common Multiple (LCM) of two numbers

The source code to find the LCM of two specified numbers is given below. The given program is compiled and executed successfully on Microsoft Visual Studio.

//C# program to find the LCM of two numbers.

using System;

class Demo
{
    static void Main()
    {
        int firstNumber=0;
        int secondNumber=0;

        int temp1=0;
        int temp2=0;

        int lcm=0;

        Console.Write("Enter the value of 1st number: ");
        firstNumber = Convert.ToInt32(Console.ReadLine());

        Console.Write("Enter the value of 2nd number: ");
        secondNumber = Convert.ToInt32(Console.ReadLine());

        temp1 = firstNumber;
        temp2 = secondNumber;

        while (firstNumber != secondNumber)
        {
            if (firstNumber > secondNumber)
            {
                firstNumber = firstNumber - secondNumber;
            }
            else
            {
                secondNumber = secondNumber - firstNumber;
            }
        }
        lcm = (temp1 * temp2) / firstNumber;

        Console.WriteLine("Least Common Multiple is : " + lcm);
    }
}

Output

Enter the value of 1st number: 9
Enter the value of 2nd number: 15
Least Common Multiple is : 45
Press any key to continue . . .

Explanation

Here, we created a class Demo that contains a Main() method. Here we found the LCM of two numbers. The LCM is the smallest number, which is the multiple of both numbers.

Console.Write("Enter the value of 1st number: ");
firstNumber = Convert.ToInt32(Console.ReadLine());

Console.Write("Enter the value of 2nd number: ");
secondNumber = Convert.ToInt32(Console.ReadLine());

temp1 = firstNumber;
temp2 = secondNumber;

while (firstNumber != secondNumber)
{
    if (firstNumber > secondNumber)
    {
        firstNumber = firstNumber - secondNumber;
    }
    else
    {
        secondNumber = secondNumber - firstNumber;
    }
}
lcm = (temp1 * temp2) / firstNumber;

In the above code, we read the value of numbers and find the LCM of both numbers and then print the result on the console screen.

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