Calculate the GCD

Problem: Calculate the GCD of Three, Four, or Five Integers. (Vb.Net ,C #)

Solution:

GCD of Two Numbers:

GCD(a,b)

Algorithm

Step 1: a modulus b = r (remainder)  If r Not Equal To Zero i.e i < > 0

Then

Step 2: a: =b and b : = r

Repeat Step 1 Till R become Zero i.e i := 0

Step 3:

GCD is b

Stop

VB Code:

 Module Module1
      Sub Main()
   Dim FirstNumber As Integer
        Dim SecondNumber As Integer
        FirstNumber = Console.ReadLine()
        SecondNumber = Console.ReadLine()
        If FirstNumber < SecondNumber Then
            Dim Temp As Integer
            Temp = SecondNumber
            SecondNumber = FirstNumber
            FirstNumber = Temp
        End If
        Dim NewMod As Integer
        Dim GCD As Integer
        NewMod = FirstNumber Mod SecondNumber
        While (NewMod > 0)
            FirstNumber = SecondNumber
            SecondNumber = NewMod
            NewMod = FirstNumber Mod SecondNumber

  End While
        GCD = SecondNumber

 Console.WriteLine(GCD)

Console.ReadLine()
    End Sub
End Module

For C# Code Convert It From 
http://www.developerfusion.com/tools/convert/vb-to-csharp/

GCD Of Three Numbers:

GCD(a,b,c)=GCD(a,GCD(b,c))

VB Code:
Module Module1
    Sub Main()
        Dim FirstNumber As Integer
        Dim SecondNumber As Integer
        Dim ThirdNumber As Integer
        FirstNumber = Console.ReadLine()
        SecondNumber = Console.ReadLine()
        ThirdNumber = Console.ReadLine()
        ' For GCD(a,b)
        If FirstNumber < SecondNumber Then
            Dim Temp As Integer
            Temp = SecondNumber
            SecondNumber = FirstNumber
            FirstNumber = Temp
        End If
        Dim NewMod As Integer
        Dim GCD As Integer
        NewMod = FirstNumber Mod SecondNumber
        While (NewMod > 0)
            FirstNumber = SecondNumber
            SecondNumber = NewMod
            NewMod = FirstNumber Mod SecondNumber

 End While
        GCD = SecondNumber
        'Now For GCD(GCD(a,b),c)
        FirstNumber = GCD
        SecondNumber = ThirdNumber
        If FirstNumber < SecondNumber Then
            Dim Temp As Integer
            Temp = SecondNumber
            SecondNumber = FirstNumber
            FirstNumber = Temp
        End If
     
        NewMod = FirstNumber Mod SecondNumber
        While (NewMod > 0)
            FirstNumber = SecondNumber
            SecondNumber = NewMod
            NewMod = FirstNumber Mod SecondNumber 
         End While
        GCD = SecondNumber
        Console.WriteLine(GCD) ' GCD Of a,b,c
        Console.ReadLine()
    End Sub
End Module

 For C# Code Convert It From 
http://www.developerfusion.com/tools/convert/vb-to-csharp/

The Code Will Become Easy If Using Function And Can perform two three and four by a little modification.

VB Code:

Module Module1
    Public Freinds() As String
    Dim COUNT As Integer
    Sub Main()
    Dim FirstNumber As Integer
        Dim SecondNumber As Integer
        Dim ThirdNumber As Integer
        FirstNumber = Console.ReadLine()
        SecondNumber = Console.ReadLine()
        ThirdNumber = Console.ReadLine()
        Dim GCD As Integer
        GCD = GetGCD(FirstNumber, SecondNumber)
        Console.WriteLine(GCD)
        FirstNumber = GCD
        SecondNumber = ThirdNumber
        GCD = GetGCD(FirstNumber, SecondNumber)
     Console.ReadLine()
    End Sub
    Private Function GetGCD(ByVal Firstnumber As Integer, ByVal SecondNumber As Integer) As Integer
        If Firstnumber < SecondNumber Then
            Dim Temp As Integer
            Temp = SecondNumber
            SecondNumber = Firstnumber
            Firstnumber = Temp
        End If
        Dim NewMod As Integer
        Dim GCD As Integer
        NewMod = Firstnumber Mod SecondNumber
        While (NewMod > 0)
            Firstnumber = SecondNumber
            SecondNumber = NewMod
            NewMod = Firstnumber Mod SecondNumber 
        End While
        Return SecondNumber
    End Function
End Module