Description

LCM (Least Common Multiple) of two numbers is the smallest number which can be
divided by both numbers.

A simple solution is to find all prime factors of both numbers, then find
union of all factors present in both numbers. Finally, return the product
of elements in union.

C/C++

/* C Program to find LCM(Least Common Multiple) */
//Save it as CalculateLCM.c

#include<stdio.h>
int main()
{
    int firstNumber, secondNumber, maxVal;

    printf("Enter first number : ");
    scanf("%d",&firstNumber);

    printf("Enter second number : ");
    scanf("%d",&secondNumber);

    maxVal = (firstNumber>secondNumber)?firstNumber:secondNumber;

    while(maxVal){

        if(maxVal%firstNumber == 0 && maxVal%secondNumber == 0)
        {
            printf("The LCM of %d and %d is %d",firstNumber,secondNumber,maxVal);
            break;
        }
        else
        {
            maxVal++;
        }
    }

    return 0;
}

Input:
Enter first number : 6
Enter second number : 8

Output:
The LCM of 6 and 8 is 24

Java

/* Java Program to find LCM(Least Common Multiple) */
//Save it as CalculateLCM.java

import java.io.*;
import java.util.Scanner;

public class CalculateLCM {

    public static void main(String[] args) {

        Scanner scanner = new Scanner(System.in);
        
        System.out.println("Enter first number : ");
        int firstNumber = scanner.nextInt();
        
        System.out.println("Enter second number : ");
        int secondNumber = scanner.nextInt();
        
        int maxVal;

        maxVal = (firstNumber>secondNumber)?firstNumber:secondNumber;

        while(true){

            if(maxVal%firstNumber == 0 && maxVal%secondNumber == 0)
            {
                System.out.println("The LCM of "+firstNumber+" and "+secondNumber+" is "+maxVal);
                break;
            }
            else
            {
                maxVal++;
            }
        }
    }
}

Input:
Enter first number : 
6
Enter second number : 
8

Output:
The LCM of 6 and 8 is 24

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