buy one get one free problem

I am making a program that calculates the price of apples (its a school one). To throw in a twist they made it so when you buy one apple you get one free. I am not aloud to use the "if" feature in this program. It is driving me crazy, I don't know how to make it so when I buy 3 apples it shows up as 2 dollars because of this whole buy one get one free thing.

Here is the code I have so far.

Code:

---

#include <cstdlib>
#include <iostream>
#include <string>

using namespace std;


double apple (double first,double second);
int main(int)
{
//vars
string username;          //Users name.
double usra,usrap=1.00;                //Users choice of Appales.
double usro,usrop=1.50;                //Users choice of Oranges.
double applecal;          //Apple calculations.
double orangecal;        //Orange calculations.
//vars end
//sig
      cout<<"*********************************************************"<<endl;
      cout<<"*                                                      *"<<endl;
      cout<<"*              Nicks Grocery store                      *"<<endl;
      cout<<"*                                                      *"<<endl;
      cout<<"*********************************************************"<<endl;
      cout<<endl;
//sig end
//Program
      cout<<"Welcome to Nick's Grocery Store."<<endl;
      cout<<endl;
      cout<<"****Todays Specials.*****"<<endl;
      cout<<"*Buy one Apple get one  *"<<endl;
      cout<<"*free!                  *"<<endl;
      cout<<"*-----------------------*"<<endl;
      cout<<"*Each Orange you buy    *"<<endl;
      cout<<"*deducts 1% off your    *"<<endl;
      cout<<"*bill.                  *"<<endl;
      cout<<"*************************"<<endl;
      cout<<"Max of 100 items per customer"<<endl;
      cout<<"*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*"<<endl;
      cout<<endl;
     
      //Asks for Users name.
      cout<<"Enter your name :";
      cin>>username;
      cout<<endl;
     
      //Asks how many Apples the User wants.
      cout<<"How many Apples would you like "<<username<<" :";
      cin>>usra;
      cout<<endl;
     
     
      //Asks how many Oranges the User wants.
      cout<<"How many Oranges woukd you like "<<username<<" :";
      cin>>usro;
      cout<<endl;
      cout<<"*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*"<<endl;
     
  applecal= apple(usra,usrap);
 
  cout<<applecal<<endl;
 
     
   

//Program end     
}

double apple(double first,double second)//Math for Apples
{
return first*second;
}

---

Maybe you could use division to see how many pairs of apples were requested and then add a dollar if the number is odd.

sorry if this comment is a bit dumb. Wouldnt you need the "if" function to do that tho?

Thx for the reply tho.

No. You could use the result of the division times the price and add the result of modulo 2 times the price. For example, 5 apples makes 5/2 (which is 2) * $1.00 plus 5%2 (which is 1) * $1.00 = $3.00. And 6 apples makes 6/2 (which is 3) * $1.00 plus 6%2 (which is 0) * $1.00 = $3.00.

first a little nitpicking:

Code:

---

int main(int)

---

what's the (int) for?

Code:

---

//vars ...

---

is there a reason they're all doubles?

Code:

---

cout<<"How many Oranges woukd you like "<<username<<" :";

---

you spelled 'Would' wrong

Code:

---

double apple(...){...}

---

why use a function... you could just as easily do that math right in the code

okay, now on to your problem... change those doubles to integers and maybe the answer will become more clear to you. Remember what happens when you use integer division:

Code:

---

#include <iostream>

int main()
{
        int apples;
        int free;
       
        std::cout<<"Enter the number of apples: ";
        std::cin>>apples;
        std::cin.ignore(1);

        free=apples/2;

        std::cout<<"You will get "<<free<<" free apples."<<std::endl;
        return 0;
}

---

Thank you guys so much :) you helped a lot. I owe you all one.

The spelling errors were a rush job sorry. The int was accidentally left there when i was doing a little trial and error with the function. Lol the function is there because they want us to do all the math in another function haha believe me if I had a choice it would all be in the code :D .

Again thanks for the help guys.
-Nick

>> believe me if I had a choice it would all be in the code

Separating things into functions that do a single job is a good thing, so making that a function is good practice.

could use a switch also..

Code:

---

switch(input)
{
case 1:
    ...
    break;
case 2:
 etc...

---

Quote:

---

Originally Posted by Daved

>> believe me if I had a choice it would all be in the code

Separating things into functions that do a single job is a good thing, so making that a function is good practice.

---

erm, since when was putting a simple multiplication into a function a good thing?

Hey, its a teacher, what do you expect?

>> erm, since when was putting a simple multiplication into a function a good thing?

Always? Of course, there are extremes, but in this case the calculation of the cost of apples given the quantity and price is perfect for separation into a function. It is just a matter of practicing good design. If you separate that into its own function, then in the future you can change the formula quickly and easily (e.g. adding buy one get one free). You can re-use that function anywhere else you want to calculate the cost of apples. Just because you don't use it in multiple places in your program yet doesn't mean you won't.

>> Hey, its a teacher, what do you expect?

IMO the teacher is correct in this case. Try to understand the reasons why.

such a simple function would be a good candidate for inline, right? And if apple was an object, then the same function could be used to calculate the price of different kinds of apple that have different prices.

I have finished the math part of the program but not I am faced with another problem :( . When I run the program and try to calculate it all it gives me these numbers and a + sign instead of just numbers like 14.00. I think it might be the variables but I have messed with them as much as I can and nothing is changing.

Here is the code.

Code:

---

#include <cstdlib>
#include <iostream>
#include <string>
#include <conio.h>

using namespace std;

float orange (int first);
float apple (int first);
int main()
{
//vars
string username;                //Users name.
int usra,usro;                  //Users choice of apples. Users choice of Oranges.
float applecal, orangecal;      //Apple calculations. Orange calculations.
float addao;                    //adding apples and oranges together.
float result;                  //The final result.
//vars end
//sig
      cout<<"*********************************************************"<<endl;
      cout<<"*                                                      *"<<endl;
      cout<<"*              Nicks Grocery store                      *"<<endl;
      cout<<"*                                                      *"<<endl;
      cout<<"*********************************************************"<<endl;
      cout<<endl;
//sig end
//Program
      cout<<"Welcome to Nick's Grocery Store."<<endl;
      cout<<endl;
      cout<<"****Todays Specials.*****"<<endl;
      cout<<"*Buy one Apple get one  *"<<endl;
      cout<<"*free!                  *"<<endl;
      cout<<"*-----------------------*"<<endl;
      cout<<"*Each Orange you buy    *"<<endl;
      cout<<"*deducts 1% off your    *"<<endl;
      cout<<"*bill.                  *"<<endl;
      cout<<"*************************"<<endl;
      cout<<"Max of 100 items per customer"<<endl;
      cout<<"*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*"<<endl;
      cout<<endl;
     
      //Asks for Users name.
      cout<<"Enter your name :";
      cin>>username;
      cout<<endl;
     
      //Asks how many Apples the User wants.
      cout<<"How many Apples would you like "<<username<<" :";
      cin>>usra;
      cout<<endl;
     
     
      //Asks how many Oranges the User wants.
      cout<<"How many Oranges would you like "<<username<<" :";
      cin>>usro;
      cout<<endl;
      cout<<"*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*"<<endl;
      cout<<applecal<<endl<<orangecal;
  applecal= apple(usra);
  orangecal= orange(usro);
             
 addao= applecal+orangecal; 
 result= usro/100*addao;
       
      cout<<endl;
      cout<<"Your total is :"<<result<<endl;
       
getch();   
return 0;   

//Program end     
}
//Math for Apples
float apple(int first)
{
return first/2+first%2;
}
//Math for Oranges
float orange(int first)
{
return first*1.50;
}

---

Thanks for reading.
-Nick

cout<<applecal<<endl<<orangecal;
applecal= apple(usra);
orangecal= orange(usro);

Do calculations, then print

applecal= apple(usra);
orangecal= orange(usro);
cout<<applecal<<endl<<orangecal;

hmm...unlucky you...would have been much easier with the 'if' function...
so scratch that off...

LOL I made a very stupid mistake there. Thank you guys again for helping me. I will let you know how the program turns out.

-Nick

Ok I know what you could do within your math, dont need to use if I belive. You want to make it so for ever orange you buy it makes the total lower right? Why not do this?
1st you need to make 4 ints: int a, int b, int c, and int d.
2nd make int a apples, int b oranges, and int c and d nothing atm.
3rd you want to know how meny oranges would take off on apples no? Then take int b - int a that would = how meny apples they will have to buy. This will be int c, make that look like this

Code:

---

c = b-a;

---

4th now take int c times lets say 1.50 (this is how much the apples cost alone)

Code:

---

c = c*1.50;

---

5th now we will do the same to b

Code:

---

b = b*1.50;

---

7th now add thes togather.

Code:

---

d = b+c;

---

8th just show what d = to and thats your totall prise. I didnt even need to use the if half. Hope that helps you.

I am having another probelem now lol. When the program prints the total it prints it like this 140 and I need it to print like this 14.00. It might be the variable types but I have changed them from int to double to float and there has been no change.

Thanks for reading.
-Nick

WAIT! forget everything I saidXD Will ok not everything. Ok in my code I found a little a problem... ok thos ints I told you to make, trun them into float like so...

Code:

---

float a;

---

Also change step 3 code to

Code:

---

c = a-b;

---

Heres what ints, long, bla bla can do with numbers.

int: used to store integers (whole numbers, no decimals/fractions)
long: used to store larger integers
double: used to store numbers with two decimal places
float: used to store numbers with multiple decimal places
char: used to store a single character

This is why you need to learn math kids:) So you dont have to use the "if" LOL. Best of luck on your work. (I am a kid, I was just playing)

I changed the variables that would use float to float but nothing happened, So then I changed them all to float and its still not working. This is very strange. LOL I am basically done with the program with one more little hurdle to jump and its the worst one. Do you guys see anything causing this that I don't see in this code?

Code:

---

#include <cstdlib>
#include <iostream>
#include <string>
#include <conio.h>

using namespace std;

float orange (int firsta);//orange prototype.
float apple (int firstb);//apple prototype.
int main()
{
//vars
string username;                //Users name.
int usra,usro;                  //Users choice of apples. Users choice of Oranges.
float applecal, orangecal;      //Apple calculations. Orange calculations.
float addao;                    //adding apples and oranges together.
float result, resultd;          //The final result. The result of the discount.
//vars end
//sig
      cout<<"*********************************************************"<<endl;
      cout<<"*                                                      *"<<endl;
      cout<<"*              Nicks Grocery store                      *"<<endl;
      cout<<"*                                                      *"<<endl;
      cout<<"*********************************************************"<<endl;
      cout<<endl;
//sig end
//Program
      cout<<"Welcome to Nick's Grocery Store."<<endl;
      cout<<endl;
      cout<<"****Todays Specials.*****"<<endl;
      cout<<"*Buy one Apple get one  *"<<endl;
      cout<<"*free!                  *"<<endl;
      cout<<"*-----------------------*"<<endl;
      cout<<"*Each Orange you buy    *"<<endl;
      cout<<"*deducts 1% off your    *"<<endl;
      cout<<"*bill.                  *"<<endl;
      cout<<"*************************"<<endl;
      cout<<"Max of 100 items per customer"<<endl;
      cout<<"*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*"<<endl;
      cout<<endl;
     
      //Asks for Users name.
      cout<<"Enter your name :";
      cin>>username;
      cout<<endl;
     
      //Asks how many Apples the User wants.
      cout<<"How many Apples would you like "<<username<<" :";
      cin>>usra;
      cout<<endl;
     
     
      //Asks how many Oranges the User wants.
      cout<<"How many Oranges would you like "<<username<<" :";
      cin>>usro;
      cout<<endl;
      cout<<"*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*"<<endl;
     
  applecal= apple(usra);//Calling the apple function/
  orangecal= orange(usro);//Calling the orange function.
             
 addao= applecal+orangecal;//Adding applecal and orangecal together.
   
 resultd= 100/usro*addao;//Finds the amount of money you have saved.

 result= resultd-=addao;//Deducts the amount you have saved from the total.
 
     
      cout<<endl;
      cout<<"Your total is :"<<result<<endl;
       
getch();   
return 0;   

//Program end     
}
//Math for Apples
float apple(int firsta)
{
return firsta/2+firsta%2;
}
//Math for Oranges
float orange(int firstb)
{
return firstb*1.50;
}

---

addao= applecal+orangecal;//Adding applecal and orangecal together.
cout << addao << endl;
resultd= 100/usro*addao;//Finds the amount of money you have saved.
cout << resultd << endl;
result= resultd-=addao;//Deducts the amount you have saved from the total.
cout << result << " " << resultd << " " << addao << end;

Figure it out, do some debugging.

The last expression looks very odd indeed.

Here is how I showed it, its just a sample, hope it helps.

Code:

---

#include <iostream>

using namespace std;

float a;
float b;
float c;
float d;

int main(){
        cout << "Enter a number: ";
        cin >> a;
        cout << "Enter a second number: ";
        cin >> b;

        c = a-b;
        c = c*1.50;
        b = b*1.50;
        d = c+b;
       

        cout << "The sum is: " << d;

        system("pause");

}

---

Can anyone help me with getting this program to display the total price correctly. It is displaying like this 144 but I want to to display this 14.40.

Thanks for reading.
-Nick

Code:

---

#include <cstdlib>
#include <iostream>
#include <string>
#include <conio.h>

using namespace std;
//prototypes
float applecal(int);//Applecal function.
float orangecal(int);//Orangecal function.
//
int main()
{
//text and background color
system("color 8F");
//text and background color end
////////////////////////////////////////////////////////////////////////////////   
//vars
int usro , usra;            //The users choice of apples and oranges.
float usrac , usroc;        //The calculated results of the users input.
float add , result;        //Adding both usrac and usroc together. Main result.

//vars end
////////////////////////////////////////////////////////////////////////////////
//sig
      cout<<"            -*********************************************************-"<<endl;
      cout<<"            **                                                      **"<<endl;
      cout<<"          ****              Nicks store                              ****"<<endl;
      cout<<"            **                                                      **"<<endl;
      cout<<"            -*********************************************************-"<<endl;
      cout<<endl;
//sig end
////////////////////////////////////////////////////////////////////////////////
//Program
      cout<<"Welcome to Nick's Store."<<endl;
      cout<<endl;
      cout<<"****Todays Specials.*****"<<endl;
      cout<<"*Buy one Apple get one  *"<<endl;
      cout<<"*free!                  *"<<endl;
      cout<<"*-----------------------*"<<endl;
      cout<<"*Each Orange you buy    *"<<endl;
      cout<<"*deducts 1% off your    *"<<endl;
      cout<<"*bill.                  *"<<endl;
      cout<<"*************************"<<endl;
      cout<<"Max of 100 items per customer"<<endl;
      cout<<"*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*"<<endl;
      cout<<endl;

   
      //Asks how many Apples the User wants.
      cout<<"How many Apples would you like :";
      cin>>usra;
      cout<<endl;
  applecal(usra);//calling applecal function.
  usrac=applecal(usra);//getting USRA variable data from applecal.
     
     
      //Asks how many Oranges the User wants.
      cout<<"How many Oranges would you like :";
      cin>>usro;
      cout<<endl;
  orangecal(usro);//calling orangecal function.
  usroc=orangecal(usro);//getting USRO variable data from orangecal.
     
      cout<<"*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*"<<endl;
      cout<<endl;
     
 add = usrac + usroc;//Adds usrac and usroc together.
 
 result = (100/usro*add)- add;
 
      cout<<"Your total is :"<<result<<endl;   
     
//end program
getch();
return 0;
}
////////////////////////////////////////////////////////////////////////////////

//applecal function.
float applecal(int first)
{
  return first/2*1.00+first%2;
}
////////////////////////////////////////////////////////////////////////////////

//orangecal function.           
float orangecal(int first)
{
      return first*1.50;
}
////////////////////////////////////////////////////////////////////////////////

---

ternary operator to the rescue.

Code:

---

delivered=(type==APPLE?number*2:number);

---

Maybe not in the spirit of the assignment, but who cares :)

Why do schools like assigning such asinine programming homework?

Quote:

---

Originally Posted by jwenting

ternary operator to the rescue.

Code:

---

delivered=(type==APPLE?number*2:number);

---

Maybe not in the spirit of the assignment, but who cares :)

---

lol thanks for the reply but I cant use anything I havent learnt yet. my teacher told me to try deviding the end resuly by 100.00, I get the correct answer and the decemals are in the right place when I do it but it still isnt displaying that extra 0 there. I think it is doing it because the 0s would just keep going and going and going if it had to display them. Is there a way I can get it to just display the last zero like this 14.40 instead of this 14.4.

Thanks for reading and sorry about spelling mistakes.

-Nick

can you use setprecision

Quote:

---

Originally Posted by Syneris

can you use setprecision

---

I just gave it a try but it still isnt showing that extra 0. :confused: I am clueless. Anyone else know whats going on with my program?

-Thanks for reading.

-Nick

Quote:

---

Originally Posted by Nick_365

I am having another probelem now lol. When the program prints the total it prints it like this 140 and I need it to print like this 14.00. It might be the variable types but I have changed them from int to double to float and there has been no change.

Thanks for reading.
-Nick

---

No offence, but you should really try figuring some of this out yourself ... so far as I can tell, besides the main body of your program, everything was done for you .... try searching through the internet. I recommend google!

No offence taken, I guess im kinda bending that rule about people doing your homework for you lol. I will google it and try my best to figure this out. Lol and if that fails then I guess I will be back here to bug you guys some more :p .

-Nick