Simple C++ code doesn't work

Can anyone tell me why my code doesn't work. I'm simply doodling with C++ and because of some knowledge in PHP, I thought I could put together a simple login program.

Code:

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#include <stdio.h>
#include <iostream.h>

int main() {

char username[10];
char password[10];
char user[10];
char pass[10];

"happy" == user;

"sad" == pass;

cout << "Please login. \n Username:";
cin >> username;

cout << "Password: ";
cin >> password;

if(user == username && pass == password) {

cout << "Login complete!";


}
else
{

cout << "Phail!";

}
}

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No matter what I type in, it always returns PHAIL!, even if if I type in the correct username and password.

Code:

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#include <iostream>
#include <string>

int main() {

    std::string username = "happy";
    std::string password = "sad";
    std::string user, pass;
    std::cout << "Please login. \n Username:";
    std::cin >> username;

    std::cout << "Password: ";
    std::cin >> password;

    if(user == username && pass == password) {

          std::cout << "Login complete!";
    }
    else
    {
          std::cout << "Phail!";

    }
}

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First: stdio.h is not needed, that is a C io header, you are using iostream which is C++.
Second: There is no iostream.h. If you see any reference to that, it's from pre-1998 C++ (before the language was standardized at all) and no longer is valid.
Third: == tests for equality, and returns true or false. = is for assigning.
Fourth: You can only assign from right to left. x = "hi"; is correct. "hi" = x; is not.
Fifth: Use std::string, not character arrays. Character arrays CANNOT be compared with ==, but std::strings can (among many other things like std::strings resistance to buffer overruns)

Here is another way to tackle your program using string instead of char arrays:

Code:

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#include <iostream>

using std::cout;
using std::endl;
using std::cin;

#include <string>

using std::string;

// main function - driver //////////////////////////////////////////////////////
//
int main ( void )
{
  string login;        // user login string
  string pass;        // user password string
  int flag = 0;        // works with logical NOT
 
  cout << "Enter your login name: ";
  cin >>login;
 
  cout << "\nEnter your password: ";
  cin >> pass;
 
  // logical AND
  if (( login == "willow" ) && ( pass == "ada" ))
  {
      cout << "\nWelcome to the network" << endl;
      flag = 10; // prevent logical NOT executing
  }
 
  // logical OR
  if (( login == "guest" ) || ( pass == "guest" ))
  {
      cout << "\nGuest login lasts for 24 hours" << endl;
      flag = 5; // prevent logical NOT executing
  }
 
  // logical NOT
  if ( !flag )
  {
      cout << "\nAcsess denied" << endl;
  }
 
  cin.get();  // freeze console window
  cin.ignore();
   
  return 0;  // indicate program ended sucsessfuly
}

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Code:

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std::

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if you write using namespace std; at the begining of your code (straight after the includes) you will not have to prefix commands with std::

Quote:

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Originally Posted by rickyoswaldiow

Code:

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std::

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if you write using namespace std; at the begining of your code (straight after the includes) you will not have to prefix commands with std::

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Importing the entire namespace is generally not reccomended.

the

Code:

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==

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mark is used in if, but if u wanna declare variable u should use

Code:

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=

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Quote:

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Originally Posted by rickyoswaldiow

Code:

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std::

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if you write using namespace std; at the begining of your code (straight after the includes) you will not have to prefix commands with std::

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Yeah, but that tends to work well for small, beginner programs but makes more advanced programs harder to read and write. I say, don't learn anything you're going to spend time unlearning later.