Where am I going wrong with Enums & Switchblocks - c++

Question

I am learning C++ as part of my course at Uni. I am not all that experienced in c++ but I have searched for possible solutions for several hours and tested hundreds of variations of code and I still cannot get this working. I believe that my use of Enums must be fundamentally wrong - I have never got them working as I intended. For this task we had to use Enums and a switch statement.
#include <iostream>
using namespace std;
enum roomType { Deluxe = 250, Twin = 150, Single = 110};
int temp;
int total;
int input = 1; int yes = 1; int no = 0;
void GetInput()
{
cin >> input;
temp = temp*input;
}
int main()
{
if (input != 0)
{
cout << "\nRoom Price Code\n------------------------------------\nDeluxe Room " << "\x9C" << "200 D\nTwin Room " << "\x9C" << "150 T\nSingle " << "\x9C" << "110 S\n\n";
cout << "Enter room type:";
GetInput();
switch (input) {
case Deluxe:
temp = Deluxe;
break;
case Twin:
temp = Twin;
break;
case Single:
temp = Single;
break;
default:
//prevents infinite loop bug
system("pause");
cout << "Entry not recognized";
main();
break;
}
cout << "\nEnter number of rooms:";
GetInput();
cout << "\nEnter number of nights:";
GetInput();
total = total + temp;
cout << "\n\x9C" << total << "\n";
cout << "More rooms? yes/no: ";
cin >> input;
main();
}
cout << "Discount? yes/no: ";
GetInput();
if (input = 1)
{
total = ((total / 100) * 75);
cout << "\n\x9C" << total << "\n";
}
cout << "your total is "<<"\x9C" << total;
system("pause");
system("cls");
return 0;
}
If the User enters a room type for instance Deluxe, the case statement always goes to default, then without the system("pause"); would proceed to get stuck in a loop.
For some reason the program seems to ignore all the cin >> input;'s after the first one. I know that it is this that is causing the looping. I have tried switching cin>> out for a getline(cin,input)alternative but that doesn't seem to work either.

Answer 1

Just compiled your code. You are not doing anything wrong for Delux. Just silly error that enum value is 250 and you are displaying 200. So while running, you are entering 200 and it goes to default.
Coming to second question that why program runs only once, its because you want it that way. The check if (input != 0) checks for input type as integer value. You might be entering 'yes' in command line and not doing any error checks. Try entering integer value.
PS: In future, please paste the code in question itself.

Answer 2

NOTE: This does not answer the users question directly; I have done that above. This is an example that is based off of one of the replies from the user and is here to demonstrate the uses of enumerations and enumerated types so that they may be able to have an easier and better understanding of them.
Here are two function prototypes that would do the same thing one uses enumerations while the other doesn't.
enum ProductType {
HARDWARE = 1,
TOOLS,
APPLIANCES,
FURNITURE,
LAWN_AND_GARDEN,
PAINT
};
// This Version Doesn't Use An Enumerated Value And Takes In An Unsigned Int
float calculateProductTotalCost( unsigned int productType, float costOfProduct, unsigned int numberOfItems );
float calculateProductTotalCost( ProductType type, float costOfProduct, unsigned int numberOfItems );
someOtherFunction() { // Could be main()
// This function has a magic number to represent the product type
calcluateProductTotalCost( 3, 1499.99f, 2 );
// This version uses the enumeration with the scope resolution operator
// to allow the calling of this function to be easier to read.
calculateProductTotalCost( ProductType::PAINT, 23.50f, 150 );
// Although I did not show any implementation for these functions
// since that is irrelevant, the importance of the two is that in
// practice these methods would be the same and perform the same
// exact calculation and operation. It is just more readable for
// another human to see your code when they have to work on it
// sometime in the future and you are not there to explain what you
// did and why you did it. It can even be a help for yourself if
// you go back to code that you have written that you have not seen
// in a few months or years. Then just by reading the Wording
// of the Enumeration you know that this value represents this specific
// object.
}
Here is another example
SoundSource {
CLAP = 1,
BANG,
GUN_SHOT,
THUNDER_BOLT,
LAUGHTER,
SCREAM,
};
bool playSound( unsigned int, bool bLoop );
bool playSound( SoundSource, bool bLoop );
someFunction() {
// Which group of function calls looks better and is easier to understand; Group A or Group B?
// Group A
playSound( 6, false );
playSound( 4, true );
playSound( 3, false );
// Group B
playSound( SoundSource::THUNDER_BOLT, true );
playSound( SoundSource::SCREAM, false );
playSound( SoundSource::LAUGH, true );
}
I hope this helps you to understand the uses of Enums; they are great for a few different things, good for switch case statements, and for allowing different data types that are usually passed in by an ID value usually an unsigned to also be represented by words that are an enumerated value. If you notice it is good practice to name all of your Values within the Enum in ALL_CAPS separating each word by an underscore; but this is also just preference, but most people will recognize this as an enum when they see all caps.

Answer 3

You have a lot of errors in this code; I structured the enum to represent an enumerated value for a switch selection, the prices are assigned in the case statements. Many times are you making a call to main(); I've never seen this done in practice! I can not say that it is invalid or illegal, but I've never seen it! I chose appropriate variable types for the right kind of concept or idea such as the cost of something being a float, when you ask user for input if there are more rooms or not or if there is a discount or not I used a bool type. Values that you know that will not be negative I used unsigned. I removed all global variables (usually bad practice). I fixed some formatting for easier readability.
Here is what I did and I have some comments to explain the changes I've made; other changes you will need to think about what I have done.
#include <iostream>
// using namespace std; // Bad Practice
enum RoomType {
NONE = 0, // NONE For Default Value - No Room Type Selected
DELUXE,
TWIN,
SINGLE,
LAST // MUST BE LAST!
};
/*void GetInput() { // Function Not Really Required In This Simple Application
cin >> input;
temp = temp*input;
}*/
int main() {
while ( true ) {
float totalCost = 0; // Renamed Variable For Better Readability
int input = 0; // Initialized To 0, We Do Not Know What The User Will Choice
std::cout << std::endl << "Room Price Code" << std::endl
<< "------------------------------------" << std::endl
<< "Deluxe Room " << "\x9C" << "250 D" << std::endl
<< "Twin Room " << "\x9C" << "150 T" << std::endl
<< "Single " << "\x9C" << "110 S" << std::endl << std::endl;
std::cout << "Please Make A Selection:" << std::endl
<< "1 - Deluxe" << std::endl
<< "2 - Twin" << std::endl
<< "3 - Single" << std::endl << std::endl;
std::cin >> input;
// You Never Declare Variable Type Of RoomType
RoomType type = static_cast<RoomType>( input ); // Cast input to RoomType
float costOfRoom = 0.0f;
switch (type) {
case NONE: {
costOfRoom = 0.0f;
break;
}
case DELUXE: {
costOfRoom = 250.0f;
break;
}
case TWIN: {
costOfRoom = 150.0f;
break;
}
case SINGLE: {
costOfRoom = 110.0f;
break;
}
default: {
std::cout << "Entry not recognized";
//main(); wrong
break;
}
} // Switch
unsigned numRooms = 0;
unsigned numNights = 0;
std::cout << std::endl << "Enter number of rooms:";
std::cin >> numRooms;
std::cout << std::endl << "Enter number of nights:";
std::cin >> numNights;
totalCost = costOfRoom * numNights * numRooms;
std::cout << "\n\x9C" << totalCost << "\n";
bool moreRooms = false;
bool hasDiscount = false;
input = 0;
std::cout << "More rooms? 1 for yes - 0 for no: ";
std::cin >> moreRooms;
if ( moreRooms ) {
std::cout << "Please Enter Number Of Rooms. ";
std::cin >> input;
totalCost += (costOfRoom * numNights * input);
}
// main(); // Wrong!
std::cout << "Discount? 1 for yes - 0 for no: ";
std::cin >> hasDiscount;
if ( hasDiscount ) {
totalCost = ((totalCost / 100) * 75);
std::cout << std::endl << "\x9C" << totalCost << std::endl;
}
std::cout << "Your total is " <<"\x9C" << totalCost << std::endl;
bool runAgain = false;
std::cout << std::endl << "Would you like to contine? 1 - yes - 0 for no:";
std::cin >> runAgain;
if ( !runAgain ) {
break;
}
} // while
system("pause");
system("cls");
return 0;
} // main