Create a class IntStr that stores a positive decimal integer as a string the maximum number of decimal digits in the string can be assumed to be only 5 digits so the maximum value that can be stored?

Answer 1

Am not sure it is a good idea to embed the integer as a string. Aside from the inefficiency of storing a 5-digit number as a string, what would be the expected result of adding two IntStr objects together? E.g., "40" + "2" could either be "42" (add), or "402" (append) depending on your intentions. And if you wished to add an IntStr and an integer, such as "40" + 2, then you'd have to convert the embedded string back to an int, perform the addition, and if the sum is less than 100000, then convert the sum back to a string. This is highly inefficient. Personally, I'd embed the integer itself and provide accessors and casts to explicitly convert it to a string on an as-required basis only, since the numeric form is likely to be far more useful to you than the string form.

However, to answer the question as it stands, the following is one possible solution.

#include<iostream>

#include<string>

#include<sstream>

class IntStr

{

private:

std::string m_string;

public:

IntStr():m_string("0") {}

IntStr(const unsigned int decimal):m_string("0")

{

set_int(decimal);

}

IntStr& operator=( const unsigned int decimal )

{

return( set_int( decimal ));

}

std::string get_int()const{ return(m_string); }

IntStr& set_int(const unsigned int decimal)

{

if( decimal<100000 )

{

std::stringstream ss;

ss<<decimal;

m_string = ss.str();

}

return( *this );

}

};

int main()

{

IntStr a; // default constructor.

a = 42; // assignment operator.

IntStr b = a; // copy constructor.

IntStr c(1000); // user-defined constructor.

IntStr d(100000); // overflow check.

std::cout<<"a = "<<a.get_int().c_str()<<std::endl;

std::cout<<"b = "<<b.get_int().c_str()<<std::endl;

std::cout<<"c = "<<c.get_int().c_str()<<std::endl;

std::cout<<"d = "<<d.get_int().c_str()<<std::endl;

}

Example output:

a = 42

b = 42

c = 1000

d = 0