### What is LCM?

LCM (Least common multiple) or LCD (lowest common denominator) is the smallest positive integer which is divisible by all numbers that is given to find LCM.

**Example:**
LCM of 8, 9, 21 is 504, Because 504 is the least common positive integer number which is divided by all given numbers i.e 8, 9, 21.

### What is GCD?

GCD (Greatest common divisor) or HCF (Highest common factor) of two numbers is the largest positive integer that divides the two numbers without any remainder.

**Example:**
GCD (8,12) is 4 because 4 is the highest number which divides both the numbers i.e 8 and 12 completely.

**Problem Statement: **Calculate the GCD and LCM of two given numbers using C#

### Code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace GCD_LCM
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine(
" #The GCD and LCM of Two Numbers#\n");
/*
* Input 1st Number :
* then Enter
* Input 2nd Number :
* PRESS SUBMIT
*/
int x = int.Parse(Console.ReadLine());
int y = int.Parse(Console.ReadLine());
Console.WriteLine(
" The GCD of Two Numbers is : "+
gcd(x, y));
Console.WriteLine(
" The LCM of Two Numbers is : "+
lcm(x, y));
}
static int gcd(int x, int y)
{
int r=0, a, b;
// a is greater number
a = (x > y) ? x : y;
// b is smaller number
b = (x < y) ? x : y;
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 is greater number
a = (x > y) ? x : y;
while (true)
{
if (a % x == 0 && a % y == 0)
return a;
++a;
}
}
}
}