Imports System

Public Module Module1

    Public Sub Main()

        Dim username, password as string ' Declaring two STRING variables - the string data.type allows us to use numbers, letters and symbols.

        Dim logincheck as boolean ' Declaring a BOOLEAN variable, meaning true or false.

        Do

            Console.WriteLine("please enter your username: ") ' Display a message to the user.

            username = console.Readline () 'This line allows us to store the user input in the USERNAME variable.

            console.WriteLine("Please enter your password: ") 'Display a message to the user.

            password = console.ReadLine() ' This line allows us to store the user input in the PASSWORD variable.

            If username = "Leonidas" and passord = "Ilovecomputing" or username = "Freeman" and password = "Englandrugby" then 'checks if Leonidas has logged in with Ilovecomputing OR Freeman has logged in with Englandrugby

                logincheck= true ' this WILL then enable the Do Loop to end because a valid user has logged in with their correct password as well.

            Else ' this it to run if any other person tries to log in (they are unregisted).

                logincheck = false 

                console.WriteLine("invalid username and/ or password. Please try again.")' tell the user that they had failed the login check.

                console.ReadLine() ' A console.Readline() on its own will just wait for the user to press any key to move on.

                console.Clear() 'clear the testing window of previous code.

            End if 

        loop until logincheck = true 'this Do Loop will repeat untill the logincheck variable is TRUE.

        console.writeline("welcome " & username) ' This code will ONLY run IF the user has logged in with a valid username and password BECAUSE it takes place

        ' AFTER the Do Loop condition 'logincheck' has been met.

            End Sub

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