Java Program to Find the GCD and LCM of two Numbers

This is java program to find the gcd and lcm of given two numbers. GCD is calculated using Euclidean Algorithm. LCM is found using factorization method.

Here is the source code of the Java Program to Find the GCD and LCM of n Numbers. The Java program is successfully compiled and run on a Windows system. The program output is also shown below.

//This is sample program to calculate the GCD and LCM of two given numbers
import java.util.Scanner;
 
public class GCD_LCM 
{
    static int gcd(int x, int y)
    {
        int r=0, a, b;
        a = (x > y) ? x : y; // a is greater number
        b = (x < y) ? x : y; // b is smaller number
 
        r = b;
        while(a % b != 0)
        {
            r = a % b;
            a = b;
            b = r;
        }
        return r;
    }
 
    static int lcm(int x, int y)
    {
        int a;
        a = (x > y) ? x : y; // a is greater number
        while(true)
        {
            if(a % x == 0 && a % y == 0)
                return a;
            ++a;
        }	
    }
 
    public static void main(String args[])
    {
        Scanner input = new Scanner(System.in);
        System.out.println("Enter the two numbers: ");
        int x = input.nextInt();
        int y = input.nextInt();
 
        System.out.println("The GCD of two numbers is: " + gcd(x, y));
        System.out.println("The LCM of two numbers is: " + lcm(x, y));
        input.close();		
    }
}

Output:

$ javac GCD_LCM.java
$ java GCD_LCM
 
Enter the two numbers: 
15
25
The GCD of two numbers is: 5
The LCM of two numbers is: 75
 
Enter the two numbers: 
5
8
The GCD of two numbers is: 1
The LCM of two numbers is: 40