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Compiles successfully but calculations give wrong answer

Stewie k (8)
Can anyone please tell me what's going on here. I'm using MSVC++ and it builds sucessfully but somewhere something is obviously messed it. Once i try to debug it just shows weird numbers.
int k=0; //could this be the problem??? since 0 would be over writing any given value. but if i leave int k; it showsa warning and MSVC would count that as an error.

Any help would be mush appreciated. Thanks



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#include "stdafx.h" //Header file section

#include <iostream>

#include <iomanip>

#include <string>

using namespace std;

//structure declaration

struct menuitemtype

{ string menuitem[10];

float menuprice[10];

};

//function prototype declaration

void getdata (menuitemtype &m, int &c);

void showmenu();

void printcheck(menuitemtype &m,int c);

int main() {//start main

menuitemtype menulist;

int c;

showmenu();

getdata (menulist, c);

printcheck(menulist, c);

system ("pause");

}//End function

//function definations

void showmenu()

{ cout<<"Welcome to Hasib Resturant"<<endl<<endl; 

cout<<"                  Menu                   "<<endl<<endl;

cout<<"1  Plain Egg"<<"\t\t"<<"$1.45"<<endl<<endl;
	
cout<<"2  Bacon and Egg"<<"\t"<<"$2.45"<<endl<<endl;

cout<<"3  Muffin"<<"\t\t"<<"$0.99"<<endl<<endl;

cout<<"4  French Toast"<<"\t\t"<<"$1.99"<<endl<<endl;

cout<<"5  Fruit basket"<<"\t\t"<<"$2.49"<<endl<<endl;

cout<<"6  Cereal"<<"\t\t"<<"$0.69"<<endl<<endl;

cout<<"7  Coffee"<<"\t\t"<<"$0.50"<<endl<<endl;

cout<<"8  Tea"<<"\t\t\t"<<"$0.75"<<endl<<endl;

cout<<"*************************"<<endl;

}//End of showmenu

void getdata(menuitemtype &m ,int &c)

{ int k=0; int choice;

cout<<"Please enter the total number of items selected by customer"<<endl;

cout<<"Please choose any number between 1 and 8 only, Thank You"<<endl;

cin>>c;

cout<<"Your total is:  ";

cin>>choice;

switch (choice)

{ case 1:m.menuitem[k]="Plain Egg";

m.menuprice[k]=1.45f; break;

case 2:m.menuitem[k]="Bacon and Egg";

m.menuprice[k]=2.45f; break;

case 3:m.menuitem[k]="Muffin";

m.menuprice[k]=0.99f;

break;

case 4:m.menuitem[k]="FrenchToast";

m.menuprice[k]=1.99f; break;

case 5:m.menuitem[k]="FruitBasket";

m.menuprice[k]=2.49f; break;

case 6:m.menuitem[k]="cereal";

m.menuprice[k]=0.69f; break;

case 7:m.menuitem[k]="coffee";

m.menuprice[k]=0.50f; break;

case 8:m.menuitem[k]="Tea";

m.menuprice[k]=0.75f; break;

}

}//End get data

void printcheck(menuitemtype &m,int c)

{ int j; float price=0.0f, tax=0.0f, total;

cout<<"          "<<endl;

for(j=0; j<c;j++);

{cout<<j<<" "<<m.menuitem[j]<<" "<<m.menuprice[j]<<endl;

price=price+m.menuprice[j];

}

tax=0.05f*price;

total= tax + price;

cout<<setprecision(2);

cout<<"Tax="<<tax<<endl;

cout<<"Your amount due ="<<total<<endl; }

//End of printcheck.
Last edited on
S G H (2638)
Use code tags (click on Edit, Select all of your code and press the <> button on the right)
MiiNiPaa (8886)
You are writing to menuitem.<>[0] in getdata() but reading from 0 to c in printcheck()
I suppose there was meant a loop in getdata()
Stewie k (8)
I'm sorry, I'm not catching it? 0 is what throwing me off. I think 0 is the one creating the problem. since int k=0 would be over writing the menu price item and messing up the calculations.

But if i leave it only as int k;
then visuall c++ throws an error stating k is unitialized?

Any solutions you can think off?
greenleaf800073 (475)
int k = 1. Mind blown
Stewie k (8)
lol at mind blown. Although thanks alot. It certainly helped alot. now if the person is ordering only one item it executes the code correctly. but say he/she wants 2 or more items it goes back to the same bizare numbers? Am i doing the calculation wrong or is the code need modification? I did try int k =1; 2; 3;....8; but same results.

Thanks
greenleaf800073 (475)
what is

#include "stdafx.h".

Can you post so I can see?
S G H (2638)
It's a visual studio default header whose only purpose is to include other files.

Back to the topic: Why not storing a table of items so you won't need all those switch/case's?
That makes it easier to spot the problem, but it's probably some operation skipping/overriding somewhere.
---
Yes, operation skipping because no matter user input, getdata only asks once what the user wants to buy. You should put a loop after the cin of c.
Last edited on
Stewie k (8)
Thanks for your advice. I edit the code and restarted from start and i agree the whole switches was rather jumbling the code. Anywho i finally got everything sorted out.

Here's my new code:

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#include "stdafx.h"
#include<iostream>
#include<string>
#include<iomanip>
using namespace std;
struct menuItemType
{string menuItem;
 double menuPrice;  
};
//function prototype declaration

void getdata( menuItemType[],menuItemType[],int&);
void showMenu( menuItemType[],int);
void printCheck(menuItemType[],int );
int main()
{
int items=0;  //write down all menu items and their respective prices 
    menuItemType menuList[]={"plain egg",1.45, 

                          "bacon and egg",2.45,

                          "muffin",0.99,

                          "french toast",1.99,

                          "fruit basket",2.49,

                          "cereal",0.69,

                          "coffee",0.50,

                          "tea",0.75

                          };
menuItemType order[10]; //write a welcome message
cout<<"Welcome to Hasib's Restaurant\n\n Please choose from the menu below\n\n     Item\t     price\n\n"; 
showMenu(menuList,8); //show menu from the data listed above
getdata(menuList,order,items);
printCheck(order,items);
system("pause");
return 0;
}
void printCheck(menuItemType order[],int items)
{int i;
double total=0,tax;
 cout<<"Your Ordered Items are:\n     Item\t     price\n"; //confirm the items ordered on a single check
 showMenu(order,items);
 for(i=0;i<items;i++)
     total+=order[i].menuPrice;
 cout<<"\nItem total    \t"<<"$"<<setprecision(2)<<fixed<<total<<endl;
 tax=total*.05; //add a 5% tax to the subtotal before prinitng receipt
 cout<<"Tax\t\t"<<"$"<<setprecision(2)<<fixed<<tax<<endl; //show the amount of tax
 cout<<"Amount Due    \t"<<"$"<<setprecision(2)<<fixed<<total+tax<<endl; //print the total amount after tax is added to the subtotal(for all the items on single order)
}
void getdata(menuItemType menu[],menuItemType order[],int& items)
{char yesno='Y';
int n;
while(toupper(yesno)=='Y')
{cout<<"Please enter your order item number below:\n "; //ask customer for order number and enter them below
cin>>n;
while(n<1||n>8)
    {cout<<"invalid item number\n\n"; //if item number is not on the menu, show an error message and ask for another input
     cout<<"Please choose any number between 1 and 8 only:\n "; //ask again for numbers given on the menu only
     cin>>n;
     }
order[items].menuItem=menu[n-1].menuItem;
order[items].menuPrice=menu[n-1].menuPrice;
items++;
cout<<"Would you like to add another item? \t (y/n)?\n "; //ask if customer wants to add more, if yes add to the order and recalculate the price at the end, if no calulate the appropriate amount
cin>>yesno;
}
}
void showMenu(menuItemType a[],int n)
{int i;
 
    for(i=0;i<n;i++)
         cout<<i+1<<".  "<<setw(16)<<left<<a[i].menuItem<<"$"<<setprecision(2)<<fixed<<a[i].menuPrice<<endl;
}

greenleaf800073 (475)
||=== cplusplus stuff, Debug ===|
s C++\cplusplus stuff\main.cpp|1|error: stdafx.h: No such file or directory|
s C++\cplusplus stuff\main.cpp||In function 'int main()':|
s C++\cplusplus stuff\main.cpp|34|warning: missing braces around initializer for 'menuItemType'|
s C++\cplusplus stuff\main.cpp|34|warning: missing braces around initializer for 'menuItemType'|
s C++\cplusplus stuff\main.cpp|34|warning: missing braces around initializer for 'menuItemType'|
s C++\cplusplus stuff\main.cpp|34|warning: missing braces around initializer for 'menuItemType'|
s C++\cplusplus stuff\main.cpp|34|warning: missing braces around initializer for 'menuItemType'|
s C++\cplusplus stuff\main.cpp|34|warning: missing braces around initializer for 'menuItemType'|
s C++\cplusplus stuff\main.cpp|34|warning: missing braces around initializer for 'menuItemType'|
s C++\cplusplus stuff\main.cpp|34|warning: missing braces around initializer for 'menuItemType'|
s C++\cplusplus stuff\main.cpp|40|error: 'system' was not declared in this scope|
||=== Build finished: 2 errors, 8 warnings ===|
greenleaf800073 (475)
Errors
Stewie k (8)
I'm not exactly sure what compiler you're using. But in microsoft visual c++ everything works perfectly.

stdafx.h // is a normal heading file for visual c++

and i'm not sure why it is throwing all those errors. i tried it on codepad and it throws those errors but dev c, it works just fine.
firedraco (6243)
On those lines you need an extra set of {} around each pair that makes up each structure.

Also, don't use system.
closed account (S6k9GNh0)
stdafx.h isn't a standard header. It's used to precompile headers in order to speed up compilation time. The name "stdafx" doesn't mean much in particular. I honestly don't see the need for the complication or the speedup given modern technology and compilation techniques.

For more info: http://en.wikipedia.org/wiki/Precompiled_header#stdafx.h
Last edited on
Stewie k (8)
Thanks for all the help guys, much appreciated!!!
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