Q. C# Program to Find Gcd of Two Numbers.

Here you will find an algorithm and program in C# programming language to find GCD of two numbers. First let us understand what is GCD.

Explanation : GCD stands for Greatest Common Divisor, GCD of two numbers is the largest number that can exactly divide both numbers. It is also called as HCF.

For Example : GCD of 60 and 45 is 15. 15 is the greatest number which can divide both 60 and 45. Therefore GCD of 60 and 45 is 15.

START
1. Input 2 Numbers A and B and declare variable GCD which holds the result.
2. Run Loop i from 1 to i <= A and i <=B
    Check if A & B are completely divisible by i or not if yes then
         Assign GCD = i
    Loop End
3. Output GCD 
STOP

C# Program to Find Gcd of Two Numbers

using System; 
class LFC { 
  static int find_gcd(int num1, int num2) 
  { 
    if (num1 == 0) 
      return num2; 
    if (num2 == 0) 
      return num1; 
    if (num1 == num2) 
      return num1; 
    if (num1 > num2) 
      return find_gcd(num1 - num2, num2); 
      return find_gcd(num1, num2 - num1); 
  } 
  
  public static void Main()  
  { 
    int num1 = 60, num2 = 45; 
    Console.WriteLine("GCD of " 
    + num1 +" and " + num2 + " is " 
    + find_gcd(num1, num2)); 
  } 
} 

Output

GCD of 60 and 45 is 15