Can functions be applied in this scenario?

[LunaticPrince]

Hello! Is there any way to make one small function out of all of the cases inside case 2 to make the code less redundant. Also, how can I make the "Would you like to do it again" a function, I tried replacing the break; with return; but I wasn't able to get the desired result.

I'm new to programming so please don't be too harsh lol

              case 2:{
                do{
                    table();
                    cout<<endl<<"Input the item code of your choice: ";
                    cin>>itcd;
                    itcd = toupper(itcd);
                    switch (itcd){
                        case 'A':{
                            if (aq<=0){
                                cout<<"OUT OF STOCK!"<<endl;
                                cout<<"Would you like to try again? Press Y for Yes and N for No: ";
                                cin>>input;
                                input=toupper(input);
                                if (input=='Y'){

                                }
                                else if (input=='N'){
                                    break;
                                }
                                break;
                            }
                            else {
                                qtty();
                                if (qty>aq){
                                    no();
                                    cout<<endl;
                                    break;
                                }
                                else if (aq>=qty){
                                    price=qty*8;
                                    pay();
                                    if (pymnt>=price){
                                        aq=aq-qty;
                                    }
                                    break;
                                }
                            }
                        }
                        case 'B':{
                            if (bq<=0){
                                cout<<"OUT OF STOCK!"<<endl;
                                cout<<"Would you like to try again? Press Y for Yes and N for No: ";
                                cin>>input;
                                input=toupper(input);
                                if (input=='Y'){

                                }
                                else if (input=='N'){
                                    break;
                                }
                                break;
                            }
                            else {
                                qtty();
                                if (qty>bq){
                                    no();
                                    cout<<endl;
                                    break;
                                }
                                else if (bq>=qty){
                                    price=qty*12;
                                    pay();
                                    if (pymnt>=price){
                                        bq=bq-qty;
                                    }
                                    break;
                                }
                            }
                        }
                        case 'C':{
                            if (cq<=0){
                                cout<<"OUT OF STOCK!"<<endl;
                                cout<<"Would you like to try again? Press Y for Yes and N for No: ";
                                cin>>input;
                                input=toupper(input);
                                if (input=='Y'){

                                }
                                else if (input=='N'){
                                    break;
                                }
                                break;
                            }
                            else {
                                qtty();
                                if (qty>cq){
                                    no();
                                    cout<<endl;
                                    break;
                                }
                                else if (cq>=qty){
                                    price=qty*15;
                                    pay();
                                    if (pymnt>=price){
                                        cq=cq-qty;
                                    }
                                    break;
                                }
                            }
                        }
                        case 'D':{
                            if (dq<=0){
                                cout<<"OUT OF STOCK!"<<endl;
                                cout<<"Would you like to try again? Press Y for Yes and N for No: ";
                                cin>>input;
                                input=toupper(input);
                                if (input=='Y'){

                                }
                                else if (input=='N'){
                                    break;
                                }
                                break;
                            }
                            else {
                                qtty();
                                if (qty>dq){
                                    no();
                                    cout<<endl;
                                    break;
                                }
                                else if (dq>=qty){
                                    price=qty*10;
                                    pay();
                                    if (pymnt>=price){
                                        dq=dq-qty;
                                    }
                                    break;
                                }
                            }
                        }
                        case 'E':{
                            if (eq<=0){
                                cout<<"OUT OF STOCK!"<<endl;
                                cout<<"Would you like to try again? Press Y for Yes and N for No: ";
                                cin>>input;
                                input=toupper(input);
                                if (input=='Y'){

                                }
                                else if (input=='N'){
                                    break;
                                }
                                break;
                            }
                            else {
                                qtty();
                                if (qty>eq){
                                    no();
                                    cout<<endl;
                                    break;
                                }
                                else if (eq>=qty){
                                    price=qty*2;
                                    pay();
                                    if (pymnt>=price){
                                        eq=eq-qty;
                                    }
                                    break;
                                }
                            }
                        }
                        default:{
                            cout<<"Please input one from the following item codes: A, B, C, D, E."<<endl;
                            cout<<"Would you like to try again? Press Y for Yes and N for No: ";
                            cin>>input;
                            input=toupper(input);
                            if (input=='Y'){

                            }
                            else if (input=='N'){
                                break;
                            }
                        }
                    }
                if (input=='N'){
                    break;
                }
                else if (pymnt>0){
                    pymnt=pymnt-pymnt;
                    cout<<pymnt;
                    break;
                }
                }
                while (x!=0);
            break;
            }

[keskiverto]

Lets look at a smaller example:

char itcd;
bool again = true;
do {
  cin >> itcd;
  switch ( itcd ) {
    case 'A':
      again = false;
      break;
    default:
  }

} while ( again );

This loop continues while again remains true. Yes, you could move code into functions:

char itcd;
bool again = true;
do {
  cin >> itcd;
  switch ( itcd ) {
    case 'A':
      if ( eq <= 0 ) {
        again = outofstock();
      }
      break;
    default:
  }
} while ( again );


// with
bool outofstock() {
  out<<"OUT OF STOCK!"<<endl;
  cout<<"Would you like to try again? Press Y for Yes and N for No: ";
  char input;
  cin>>input;
  input=toupper(input);
  return input != 'N';
}

You have (at least) nested

switch
  loop
    switch

You do have a lot of breaks. Most of them seem to merely jump to the end of the inner switch.

Some end the loop. Which asks a question, which shows intent better

  if ( x ) break;
} while ( y );
// OR
} while ( y && !x );

The outer switch could indeed be simpler, if you can move nested bits into functions:

switch ( x ) {
  // cases
  case 2:
    result = casetwo(/*data*/);
    break;
  //cases
}
// use the result 

The only question is, what data to pass in and out.

[LunaticPrince]

Thank you for the quick reply!

Do you mind me asking what this does? I've read about return; but I'm not really sure how it works

return input != 'N';

Also, what makes the second option better?

 if ( x ) break;
} while ( y );
// OR
} while ( y && !x );

Thank you again for replying :)

[keskiverto]

Some functions always return a value. Other functions return no value (void).
See http://www.cplusplus.com/doc/tutorial/functions/

bool outofstock() // promise to return a bool value
{
  // code
  return foo; // foo is a bool, or converts to bool
}

What is better, depends,

On one there is a loop that repeat as long as the condition is true:

do {
  // things to repeat
} while ( condition );

To repeat or not is all based on one expression on one line.

On the other one still has some condition, but that is not the only point of exit:

do {
  // things to repeat
    break;
  // things to repeat in some cases
    break;
  // things to repeat, unless
} while ( condition );

"Correct" and "easy to understand" are things to favor. The latter is of course subjective. Complex, hard to read code is much more difficult to make correct and keep correct.

do {
  // code
  if ( x ) break; // loop will end, IF x==true
} while ( y ); // loop will end, IF y!=true
// summary:
// loop ends, IF (x==true OR y==false) 

do {
  // code
} while ( !x && y );
// summary:
// loop continues, IF (x==false AND y==true) 

loop continues == loop does not end
(x==false AND y==true) == NOT (x==true OR y==false) Boolean logic.