please help me with my logic... so I am making a user login$...$ and it works... however... lets say i login and then close the program and a new user tries to login and they dont exist in the $.$txt file, the program just kind of bypasses the fact they have to register and logs in the last person who was logged in$...$

i want some kind of logic that only logs in the user IF they exist... and if they dont then they have to register before they continue, but i also want if they do login for it to continue to the body; my mind just cant wrap around the logic

#include

#include

#include

#include

using namespace std;

class User

$\{$

protected:

char username$[50]$;

char password$[50]$;

public:

const char$*$ getName$()$ const

$\{$

return username;

$\}$

void Register$()$

$\{$

ofstream fs$("$login$.$txt$",$ ios::app$)$;

cout $<<"$ Enter username: $"$;

cin $>>$ username;

cout $<<"$ Enter password: $"$;

cin $>>$ password;

fs $<<$ endl $<<$ username $<<""<<$ password;

cout $<<$ "User registered successfully" $<<$ endl $<<$ endl;

fs$.$close$()$;

$\}$

void login$($char un$[],$ char pw$[])$

$\{$

int k $=0$;

ifstream fs$("$login$.$txt$")$;

while $(!$fs$.$eof$())$

$\{$

fs $>>$ username $>>$ password;

if $($strcmp$($un$,$ this$->$username$)==0$ && strcmp$($pw$,$ this$->$password$)==0)$

$\{$

cout $<<"$ Login Sucessful" $<<$ endl $<<$ endl;

k $=0$;

$\}$

else

k $=1$;

$\}$

if $($k $==1)$

cout $<<"$ User does not exist. Please Register.

$"$;

fs$.$close$()$;

$\}$

$\}$;

#include "User.cpp$"$

int main$()\{$

User l$1$;

bool loggedIn $=$ false;

while $(!$loggedIn$)$

$\{$

char username$[50],$ password$[50]$;

int ch;

cout $<<"********$ Welcome to SMS $*********"$;

cout $<<"$

$1.$ Login

$2.$ Create an Account" $<<$ endl $<<$ endl;

cout $<<"$ Enter choice: $"$;

cin $>>$ ch;

cout $<<$ endl;

switch $($ch$)$

$\{$

case $1$:

cout $<<"$ Username : $"$; cin $>>$ username;

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

l$1.$login$($username$,$ password$)$;

loggedIn $=$ true;

break;

case $2$:

l$1.$Register$()$;

loggedIn $=$ false;

break;

default:

std::cout $<<$ "Invalid choice. Please try again.

$"$;

$\}$

$\}$

$//$body of the program

cout $<<$ "Welcome $"<<$ l$1.$getName$()<<".$ You are now logged in$.$ Continue with the program...

$"$;

$\}$

I think it has something to do in main, but it could be in the login function... please try the program out and you will see what I mean with the logic