Question

Using C++ emulate a sign in procedure.

At this stage we do not have a file yet that contains those username and password records.

You'll hard code a user name and password, and using selection and some string manipulation or comparison you'll go through the sign in process with your user.

Some things to consider are: Let us know where we're signing in.

Other interactions return to you a black screen with little other than a cursor.

How is your user going to know that they are signing in at the right place?

Your user may / will not have a clue as to how to use your system - use the space after your Company Heading to explain what they are doing. Notice how precise the screen captions there are. You have to guide your user through the interaction until they are familiar with the process.

If I try to authenticate as TRAN that the same as tran or TrAN or TraN? Nope. What string manipulations or operations have we seen that you can use here?

Let's assume you can goof your sign in 2 times before you are booted out. You'll need a mechanism to keep track of those failed sign-in attempts.

If you keep all of your previous outputs to screen present, your terminal window will get awfully crowded awfully fast. You'll want to clear the screen in between interactions (like other programs do ) There are two methods here to do so.

Answer 1

Answer:

1. Code For Login and Registration System in C++

#include <iostream>
#include<string>
using namespace std;
int failed_login_attempts = 3, failed_correct_password_attempts = 3;
string username, password;
bool new_user = false;
/**
* Function to get username and password
*
* @param null
*
* @return void
*/
void getUserData(){
   cout<<"Enter username"<<endl;
   cin>>username;
   cout<<"Enter password"<<endl;
   cin>>password;
}// end getUserData()

/**
* Function to get username and password and check for valid login to the system
*
* @param null
*
* @return void
*/
void isLoggedIn(){
   login_again:
   // Take Username and password
   getUserData();
   // check for valid user credentials
   if(username == "test"){
       goto old_user_credentials;
       new_user_credentials:
       cout<<"Enter your password again "<<endl;
       cin>>password;
       old_user_credentials:
       if(password == "demo"){
           cout<<"Succesfully logged in"<<endl;
       }else{
           if(new_user == true){
               failed_correct_password_attempts = failed_correct_password_attempts - 1;
               if(failed_correct_password_attempts > 0){
                   cout<<"You have "<<failed_correct_password_attempts<<" attempts left to enter the correct password to sign in to the system"<<endl;  
                   goto new_user_credentials;
               }else{
                   cout<<"Sorry, You have entered invalid password"<<endl;
                   exit(0);
               }
           }else{
               failed_login_attempts = failed_login_attempts - 1;
               if(failed_login_attempts > 0){
                   cout<<"You have "<<failed_login_attempts<<" attempts left to sign in to the system"<<endl;
                   goto login_again;
               }else{
                   cout<<"Sorry, You have entered invalid credentials"<<endl;
                   exit(0);  
               }
           }
       }
   }else{
       failed_login_attempts = failed_login_attempts - 1;
       if(failed_login_attempts > 0){
           cout<<"You have "<<failed_login_attempts<<" attempts left to sign in to the system"<<endl;
           goto login_again;
       }else{
           cout<<"Sorry, You have entered invalid credentials"<<endl;
           exit(0);  
       }
   }
}// end isLoggedIn()

/**
* Function for the starting point of the program in C++
*
* @param null
*
* @return int
*/
int main(int argc, char** argv) {
   int choice;
   cout<<"==================================================================== Simple Login and Registration System =================================================="<<endl;
   // Menu System for Login and Registratio System in C++
   while(true){
       cout<<"1: Login"<<endl;
       cout<<"2: Register"<<endl<<"3: Exit the program"<<endl<<"Enter your choice"<<endl;
       cin>>choice;
       switch(choice){
           case 1 :
               isLoggedIn();
               break;
           case 3 :
               exit(0);
               break;
           case 2 :
               getUserData();
               if (std::string::npos != password.find_first_of("0123456789")) {
                   cout<<"User Registered Successfully"<<endl;
                   new_user = true;
               }else{
                   cout<<"Password must contain a number"<<endl;
               }
               break;
       }
   }
   return 0;
}// end main(int argc, char** argv)