Thread: Can I use void to write a function to test for true or false?

My password program checker program works fine but now I would like to add a function that I can use to check that username and password are correct. Is my general coding ok or is it just plain wrong? The pass_checker is my question. I am now getting an error: expected ')' before 'pass_checker' and else without a previous if. I don't get these errors when I don't use void pass_checker. Thanks in advance.

Code:

#include <iostream>
#include <string>
using namespace std;
string username;
string password;


void user_pass ()
{
        cout << "Enter your username: " << endl;
        cin >> username;
        cout << "Enter your password: " << "\n";
        cin >> password;
}


void pass_checker ()
{
    ( username == "root" && password == "1") || (username == "beer" && password == "2");
}


int main()








{
  int i = 0;
    user_pass ();
      if pass_checker (); //(( username == "root" && password == "1") || (username == "beer" && password == "2"))
           { cout << "Access allowed" << "\n"; }
       else


       {
           cout << "Bad username or password. Denied access!" << "\n";




            while ( i < 2 )
            {
                user_pass ();
                  if (( username == "root" && password == "1") || (username == "beer" && password == "2"))
                   { cout << "Access allowed" << "\n"; }
                   else
                    { cout << "Bad username or password. Denied access!" << "\n";}


                    i++;
            }
        }
}

For your own clarity and those who are to read you code, please format it properly. If you use tabs in your editor, it most likely offers a feature to replace those with 4 spaces.

So instead of:

Code:

int main()


                                                      {





                    cout <<


                          "Hello World!"



     << endl;


}

... consider:

Code:

int main()
{
    cout << "Hello World!" << endl;
}

You get the idea.

While user_pass and pass_checker might be able to access your variables, this is due to them being declared globally. I would advise against doing this, as it is considered back practice in most cases and makes your program harder to reason about. So declare username and password locally inside main in your example.

Using functions involves learning about passing variables to them. So before rushing into this, I suggest you consult the web on how to do that.

If you want to use pass_checker as a condition for an if statement, it should return a bool value.

Code:

bool pass_checker(const string& username, const string& password)
{
    return (username == "root" && password == "1") || (username == "beer" && password == "2");
    // ^ returns the outcome of your expression; either true or false.
}

Yes, something does not add up.
No compilation.
And I do not quite understand this.

Ошибка 1 error C2061: синтаксическая ошибка: идентификатор "pass_checker" d:\rozbir\ falsetrue\falsetrue\falsetrue\falsetrue1.cpp 25 1 Falsetrue

I like your code.
I added brackets and a pause.
Thank you for the task.

Code:

  
#include<iostream>
#include<string>
usingnamespace std; 
string username; 
string password; 
void user_pass () { 
cout << "Enter your username: " << endl; 
cin >> username; 
cout << "Enter your password: " << "\n"; 
cin >> password; } 
bool pass_checker(const string& username, const string& password)
{ return (username == "root" && password == "1") || (username == "beer" && password == "2"); // ^ returns the outcome of your expression; either true or false. 
} 
　
　
int main() 
{ int i = 0; 
user_pass (); 
if (pass_checker (username,password)) //(( username == "root" && password == "1") || (username == "beer" && password == "2")) 
{ cout << "Access allowed" << "\n"; } 
else 
{ cout << "Bad username or password. Denied access!" << "\n"; 
while ( i < 2 ) 
{ user_pass (); 
if (( username == "root" && password == "1") || (username == "beer" && password == "2")) 
{ cout << "Access allowed" << "\n"; } 
else
{ cout << "Bad username or password. Denied access!" << "\n";
} 
i++;
} 
} 
system("Pause"); 
　
return 0;
}