Java program to find the LCM of two numbers

L.C.M. or Least Common Multiple of two values is the smallest positive value which the multiple of both values.

For example multiples of 3 and 4 are:

3 → 3, 6, 9, 12, 15 ...
4 → 4, 8, 12, 16, 20 ...

The smallest multiple of both is 12, hence the LCM of 3 and 4 is 12.

Algorithm

• Initialize A and B with positive integers.
•  Store maximum of A & B to the max.
•  Check if max is divisible by A and B.
•  If divisible, Display max as LCM.
•  If not divisible then step increase max, go to step 3.

Example

public class LCMOfTwoNumbers {
   public static void main(String args[]){
      int a, b, max, step, lcm = 0;
      Scanner sc = new Scanner(System.in);
      System.out.println("Enter first number ::");
      a = sc.nextInt();
      System.out.println("Enter second number ::");
      b = sc.nextInt();

      if(a > b){
         max = step = a;
      }
      else{
         max = step = b;
      }

      while(a!= 0) {
         if(max % a == 0 && max % b == 0) {
            lcm = max;
            break;
         }
         max += step;
      }
      System.out.println("LCM of given numbers is :: "+lcm);
   }
}

Output

Enter first number ::
6
Enter second number ::
10
LCM of given numbers is :: 30