Java Program to Find LCM of two Numbers

In this article, we will understand how to calculate the LCM of two numbers in Java. Lowest Common Multiple (LCM) of two numbers is the smallest positive integer that is evenly divisible by both the numbers.

Below is a demonstration of the same −

Input

Suppose our input is −

24 and 18

Output

The desired output would be −

The LCM of the two numbers is 72

Algorithm

Step1- Start
Step 2- Declare three integers: input_1, inpur_2 and sum
Step 3- Prompt the user to enter two integer value/ Hardcode the integer
Step 4- Read the values
Step 5- Using a while loop from 1 to the bigger number among the two inputs, check if the 'i'value divides both the inputs without leaving behind reminder.
Step 6- Display the 'i' value as LCM of the two numbers
Step 7- Stop

Example 1

Here, the input is being entered by the user based on a prompt. You can try this example live in ourcoding ground tool .

import java.util.Scanner;
public class LCM {
   public static void main(String[] args) {
      int input_1 , input_2 , lcm;
      Scanner scanner = new Scanner(System.in);
      System.out.println("A scanner object has been defined ");
      System.out.println("Enter the first number: ");
      input_1 = scanner.nextInt();
      System.out.println("Enter the second number: ");
      input_2 = scanner.nextInt();
      lcm = (input_1 > input_2) ? input_1 : input_2;
      while(true) {
         if( lcm % input_1 == 0 && lcm % input_2 == 0 ) {
            System.out.printf("The LCM of %d and %d is %d.", input_1, input_2, lcm);
            break;
         }
         ++lcm;
       }
   }
}

Output

A scanner object has been defined
Enter the first number:
24
Enter the second number:
18
The LCM of 24 and 18 is 72.

Example 2

Here, the integer has been previously defined, and its value is accessed and displayed on the console.

public class LCM {
   public static void main(String[] args) {
      int input_1 , input_2 , lcm;
      input_1 = 24;
      input_2 = 18;
      System.out.println("The first number is " + input_1);
      System.out.println("The second number is " + input_2);
      lcm = (input_1 > input_2) ? input_1 : input_2;
      while(true) {
         if( lcm % input_1 == 0 && lcm % input_2 == 0 ) {
            System.out.printf("\nThe LCM of %d and %d is %d.", input_1, input_2, lcm);
            break;
         }
         ++lcm;
      }
   }
}

Output

The first number is 24
The second number is 18
The LCM of 24 and 18 is 72.