exceptions

[AnaMariaB]

Write a C + + program that asks the user a value for the width; and then displays the corresponding square area. If the width is not an integer, the situation will be treated as an exception. Exception handling subroutine will restore the width to 0 and will warn the user of the mistake made.
if anybody can help me tyo solve this with or without classes.
thank you

[Catfish666]

Do you know how to throw and catch exceptions?

You throw and catch them by their type. Because each exception needs to have a different type, the C++ library offers an std::exception class that you can derive your own exceptions from, to make your job easier.

http://www.cplusplus.com/reference/exception/exception/exception/

#include <exception>
#include <iostream>

class ExampleException: public std::exception
{
public:

    const char * what() const throw()
    {
        return "your error message goes here";
    }
};

void ex_function()
{
    throw ExampleException();
}

int main()
{
    try
    {
        ex_function();
    }
    catch (const ExampleException &ee)
    {
        std::clog << "Exception caught: " << ee.what() << ".\n";
    }
}

Exception caught: your error message goes here.

[Smac89]

int width;
for (std::cout << "Enter a value: "; !(std::cin >> width); std::cout << "Enter a value: ")
{
    std::cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n');
    std::cin.clear();
}