Need to explain all the cases according to the errors

Question

1.00/5 (2 votes)

See more:

#include<iostream>

using namespace std;

class Shape{

protected:

float w,h;

void get()

{

cin>>w>>h;

}

 

Shape(float a)

{

w=a;

}

};

class Rectangle: public Shape{

protected:

void area{

cout<<w*h<<endl;

}

};

int main()

{

rectangle R;

R.get();

R.area();

return 0;

}

What I have tried:

I found 3 error , I need to explain why show this error .

Posted 31-Jul-22 19:02pm

N Hasan

Updated 1-Aug-22 5:30am

Add a Solution

Comments

Sandeep Mewara 1-Aug-22 1:09am

And the query is? Seems you missed sharing what you tried and are stuck with.

N Hasan 1-Aug-22 1:11am

When i run this code ,i found 3 error , but i need to know details about 3 error...

Dave Kreskowiak 1-Aug-22 1:30am

So are you going to tell everyone what the errors are or just let everyone guess?

2 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

OriginalGriff · Accepted Answer · 2022-07-31T19:47:00

Start by picking a braces style and sticking to it, and indenting your code so it's at least a bit readable:

C++

#include<iostream>

using namespace std;

class Shape
    {
    protected:
    float w,h;
    void get()
        {
        cin>>w>>h;
        }
    
    Shape(float a)
        {
        w=a;
        }
    };

class Rectangle: public Shape
    {
    protected:
    void area
        {
        cout<<w*h<<endl;
        }
    };
    
int main()
    {
    rectangle R;
    R.get();
    R.area();
    return 0;
    }

Then look at your error messages:

main.cpp:46:1: error: variable or field ‘area’ declared void

area is either a field also known as a variable) or a method. If it's a field, it can't be void and if it's a method it needs a parameter list (even an empty one) denoted by '(' and ')' characters.
Since you try to call it, I'll assume it's a method. In which case, this is wrong:

void area
    {
    cout<<w*h<<endl;
    }

It should be this:

void area()
    {
    cout<<w*h<<endl;
    }

You should expect to get syntax errors every day, probably many times a day while you are coding - we all do regardless of how much experience we have! Sometimes, we misspell a variable, or a keyword; sometimes we forget to close a string or a code block. Sometimes the cat walks over your keyboard and types something really weird. Sometimes we just forget how many parameters a method call needs.

We all make mistakes.

And because we all do it, we all have to fix syntax errors - and it's a lot quicker to learn how and fix them yourself than to wait for someone else to fix them for you! So invest a little time in learning how to read error messages, and how to interpret your code as written in the light of what the compiler is telling you is wrong - it really is trying to be helpful!

So read this: How to Write Code to Solve a Problem, A Beginner's Guide Part 2: Syntax Errors[^] - it should help you next time you get a compilation error!

merano99 · Accepted Answer · 2022-08-01T05:30:00

Quote:
I found 3 error , I need to explain why show this error .

The errors are not specified, but it would be interesting to know which three you have already noticed yourself. I'm getting at least double that and adding the annotations it's even more.

C++

class Shape
{
public:                     //!1! Constructor must be public!
	Shape(float a)
	{
		w = a;
	}
	void get()              //!2! Member hast to be public
	{
		cin >> w >> h;
	}
protected:
	float w, h;
};

class Rectangle : public Shape
{
public: 
	Rectangle(float a):Shape(a) {};  //!3! Missing Constructor
// protected:                   //!4! Member hast to be public  
	void area()                 //!5! missing brackets
	{
		cout << w*h << endl;
	}
};

int main()
{
	Rectangle R(1.0);     //!6! spelling wrong + constructor mismatch
	R.get();
	R.area();
	return 0;
}

Remarks:
When accessing Rectangle::area(), w and h are accessed.Here it should be ensured that the member variables w and h are initialized.This is usually done in the constructor. When entering, there is no indication to the user of what to enter.Also, the values are never checked.For example, they could be negative! In the Shape::get() method, w and h are overridden, why is w already set in the constructor when w is overridden anyway?

Need to explain all the cases according to the errors

2 solutions

Solution 1

Solution 2

Add your solution here

Preview 0