cin.get() is taking input from previous cin.get() - c++

Question

I'm super new to this, and am trying to code a simple shop interface for a CLI adventure game.
The problem I'm having is in between uses of cin.get(). I've read another post but don't understand what's being said. Can someone explain like I'm 5?
I use cin.get() once in the MainMenu() to wait for Enter to continue. This punishes the player's health if they do anything other than press Enter.
I then move forwards to the Introduction(), where I'm trying to pull the same trick, but it carries the input from cin.get() from the MainMenu() function.
The other code in main() is just keeping track of the character's health and stopping the program if it reaches 0 by way of another function.
#include <iostream>
#include <ctime>
#include <string>
using namespace std;
int MainMenu()
{
cout << "\nPress the ENTER key\n";
char Input = cin.get();
if (Input == '\n')
{
return 0;
}
else if (Input != '\n')
{
cout << "I meant ONLY the ENTER key... Oh well its your health pool.\n";
CharHealth(-2);
cout << "You took 2 damage. \nYou now have " << CharHealth(0) << "Health.\n";
return 0;
}
}
int Introduction()
{
cout << "you awake in a puddle, walk to town. \nPress [ENTER]";
char Input = cin.get();
if (Input != '\n')
{
cout << "\nfor real?\nTake Another 2 Damage\nwhat did you think?... Idiot" ;
CharHealth(-2);
return 0;
}
else
{
return 0;
}
}
int main()
{
MainMenu();
Introduction();
while (CharHealth(0) > 0)
{
cout << "winner";
return 0;
}
cout << "\n You died. idiot.";
return 0;
}
Don't judge my story telling, everything is still placeholders right now.
My console just reads:
Press the ENTER key
asdf
I meant ONLY the ENTER key... Oh well its your health pool.
You took 2 damage.
You now have 1Health.
you awake in a puddle, walk to town.
Press [ENTER]
for real?
Take Another 2 Damage
what did you think?... Idiot
You died. idiot.
C:\Users\KR's\Documents\text Shop>

Answer 1

cin.get() reads 1 char at a time. So, for example, if the user types in asdf, then the next cin.get() will read and return a, leaving sdf in cin's input buffer. Then the next cin.get() will read and return s, leaving df in cin's input buffer. And so on. Your code is not taking that into account. There is only 1 input buffer in cin, there is no per-function input buffer, like you are expecting.
If the user does not type in what you want, use cin.ignore() to discard the unwanted input. For example:
...
#include <limits>
...
int MainMenu()
{
cout << "\nPress the ENTER key\n";
char Input = cin.get();
if (Input != '\n')
{
cin.ignore(numeric_limits<streamsize>::max(), '\n'); // <-- ADD THIS
cout << "I meant ONLY the ENTER key... Oh well its your health pool.\n";
CharHealth(-2);
cout << "You took 2 damage. \nYou now have " << CharHealth(0) << "Health.\n";
}
return 0;
}
int Introduction()
{
cout << "you awake in a puddle, walk to town. \nPress [ENTER]";
char Input = cin.get();
if (Input != '\n')
{
cin.ignore(numeric_limits<streamsize>::max(), '\n'); // <-- ADD THIS
cout << "\nfor real?\nTake Another 2 Damage\nwhat did you think?... Idiot" ;
CharHealth(-2);
}
return 0;
}

Answer 2

cin.get() reads only one character and leave other inputted things on the stream.
It seems you want to read until \n is read. It can be done like this:
int MainMenu()
{
cout << "\nPress the ENTER key\n";
int count = 0;
while (cin.get() != '\n') count++;
if (count == 0)
{
return 0;
}
else if (count != 0) // we won't need this if statement, but I respect you
{
cout << "I meant ONLY the ENTER key... Oh well its your health pool.\n";
CharHealth(-2);
cout << "You took 2 damage. \nYou now have " << CharHealth(0) << "Health.\n";
return 0;
}
}
(warning: This code will fail into an infinite loop if we get EOF before newline)