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Do While Error

lmwbxr (6)
Hi, I am new here. I am not looking for this to be solved for me but for a suggestion of how to fix this :-) -- I took a for loop problem, and tried to convert it to a 'do while'.

The goal is for the sandwich order to calculate cost, but also ask the user if they want to continue if input that is not choice : 1, 2 or 3. Also - should I be making the choices int vs string?

Thanks in advance for any help. 

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#include <iostream>
#include <string>
#include <limits>

int cost;
int sandwich;
using namespace std;
int main(void)

{

   cout << "1. Ham - $4\n"
      << "2. Veggie - $3\n"
      << "3. Rat - $2\n"

      do
      {
         cout << "Choose a sandwich: (1,2 or 3, others to exit)" << "\n";
         cin >> sandwich;
         while ((sandwich > 0) && (sandwich < 4));

         do
         {
            cout << "Invalid Order)" << "\n";

            while ((sandwich < 0) && (sandwich > 4));

         }
         if (sandwich == "1. ham")
            cost = 4;
         else if (sandwich == "2. veg")
            cost = 3;
         else
            if (sandwich == "3. rat")
               cost = 2;
            else
               return (std::cout << "Invalid sandwich\n"));

               cout << "The cost is $" << cost << '\n';
      }


   return 0;
[/code]
Last edited on
lastchance (6980)
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int main()             // <==== don't put a semicolon here
{                      // <==== starts the main function statements

//  Do your stuff here

}                      // <==== ends the main function statements



It looks like you tried to write far too much code at once.
Last edited on
lmwbxr (6)
That is a reasonable assessment lol. I will start there.

Thank you. I am dizzy from reading stack overflow rn.

George P (5605)
A couple of things to note:

1.
PLEASE learn to use code tags, they make reading and commenting on source code MUCH easier.

http://www.cplusplus.com/articles/jEywvCM9/
http://www.cplusplus.com/articles/z13hAqkS/

HINT: you can edit your post and add code tags.

Some formatting & indentation would not hurt either

(you tried to use code tags, but inserting the space between / and code torched the tags.

2. Your code with code tags and formatting:
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#include <iostream>
#include <string>
#include <limits>

int main(void);
int cost;
int sandwich;
using namespace std;
//I keep getting "expected unqualified ID" at the below bracket. My build then fails.
{

   cout << "1. Ham - $4\n"
      << "2. Veggie - $3\n"
      << "3. Rat - $2\n"

      do
      {
         cout << "Choose a sandwich: (1,2 or 3, others to exit)" << "\n";
         cin >> sandwich;
         while ((sandwich > 0) && (sandwich < 4));

         do
         {
            cout << "Invalid Order)" << "\n";

            while ((sandwich < 0) && (sandwich > 4));

         }
         if (sandwich == "1. ham")
            cost = 4;
         else if (sandwich == "2. veg")
            cost = 3;
         else
            if (sandwich == "3. rat")
               cost = 2;
            else
               return (std::cout << "Invalid sandwich\n"));

               cout << "The cost is $" << cost << '\n';
      }


   return 0;

Your have more problems than just the do...while loops.

1. you can't redefine the main function. (the ; at the end is the killer)

2. your opening main function bracket is misplaced.

3. you are missing an ending bracket.

4. you are missing a ; when printing out your menu.

5. you have two do blocks, yet have only one while statement.

lmwbxr (6)
Thanks for the info. I will run down this list and see if I can fix this code. Also - noted on the formating.

Lisa
George P (5605)
That error list may not be complete, it is just what was obvious from the error list Visual Studio vomited up and what I noticed at a quick glance.

When confronted by multiple compile errors tackling/fixing the errors one at a time, preferably from the top down, more often than not will make some or all of following errors disappear.

In C++ int main(void) is not invalid, but not recommended. It is the C way to write the main function that doesn't use any parameters passed to it by the OS.

https://stackoverflow.com/questions/12225171/difference-between-int-main-and-int-mainvoid
lmwbxr (6)
It's enough to get it closer to completion. Thanks for the links as well.

lmwbxr (6)
OK - I made several of the changes suggested, and a few of my own. I think I am close - but still no build.

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#include <iostream>
#include <string>
#include <limits>

using namespace std;
int main(void)
{
    const double Ham = 4;
    const double Veggie = 3;
    const double Rat = 2;
    
    int sandwich;
    int cost;

    do
    {
    cout << "1. Ham - $4\n"
      << "2. Veggie - $3\n"
    << "3. Rat - $2\n";

     
         cout << "Choose a sandwich: (1,2 or 3, others to exit)" << "\n";
         cin >> sandwich;
        
        //Validate choice
        while ((sandwich < 1) || (sandwich <3))
        {
            cout << "Please enter 1, 2, or 3:";
            cin >> sandwich;
        }
      
        //Calculate cost based on user input.
        if (sandwich == 1)
           cost = 4;
        else if (sandwich == 2)
           cost = 3;
        else
           if (sandwich == 3)
              cost = 2;
           else
            
             //  return cout << "Invalid sandwich\n";

              cout << "The cost is $" << cost << '\n';


   return 0;
}


}
ne555 (10692)
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do
{// <-- open brace
   //statements...
} // <-- close brace
while( condition ); // <-- semicolon


also, let your IDE do the indentation.
lmwbxr (6)
Thanks. I have something functional now. I appreciate all the help. I will be staying in this forum to keep learning. :-)
Daathwi (3)
This could be the way that you are probably thinking about input and output execution..
I made some changes in your code.. 
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#include <iostream>
#include <string>
#include <limits>

int cost;
int sandwich;
using namespace std;
int main()

{

   cout << "1. Ham - $4\n"
      << "2. Veggie - $3\n"
      << "3. Rat - $2\n";

      do
      {
         cout << "Choose a sandwich: (1,2 or 3, others to exit)" << "\n";
         cin >> sandwich;
         
         if (sandwich == 1) {
                cost = 4;
                cout << "The cost is $" << cost << '\n';
         }
         else if (sandwich == 2) {
                cost = 3;
                cout << "The cost is $" << cost << '\n';
         }
         else {
            if (sandwich == 3) {
                cost = 2;
                cout << "The cost is $" << cost << '\n'; 
            }
            else
                cout << "Invalid sandwich\n";
         }    
      }
      while (sandwich>0 && sandwich<4);
      
      if((sandwich < 0) || (sandwich > 4))
              cout << "invalid order ! " << endl;

   return 0;
}
Last edited on
seeplus (6464)
Your final do loop doesn't really do anything as sandwich can't be both < 0 and > 4 at the same time!

Possibly:

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#include <iostream>

using namespace std;

int main() {
	cout << "1. Ham - $4\n"
		<< "2. Veggie - $3\n"
		<< "3. Rat - $2\n";

	int sandwich {}, cost {};

	do {
		cout << "Choose a sandwich: (1,2 or 3, others to exit): ";
		cin >> sandwich;

		if (sandwich == 1) {
			cost = 4;
			cout << "The cost is $" << cost << '\n';
		} else if (sandwich == 2) {
			cost = 3;
			cout << "The cost is $" << cost << '\n';
		} else {
			if (sandwich == 3) {
				cost = 2;
				cout << "The cost is $" << cost << '\n';
			}
		}
	} while (sandwich > 0 && sandwich < 4);

	cout << "Thanks for ordering. Bye\n";
}

Daathwi (3)
yeah, there should be || between the each cases..

Also there need not be the loop also in that case (message is updated now)
seeplus (6464)
Are you sure about L38 in your update post???

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