session_4_ex (연산자 오버로딩)_문제

The goal of this exercise is to build an infinite calculator. As you know (or not), each type of number that your are using has a limited space in memory. With the 64 bits architecture you can store pretty huge numbers.

For example:

Int32
32-bit signed integer
Min/Max Value: -2,147,483,648 / 2,147,483,648

Int64
64-bit signed integer
Min/Max Value: -9,223,372,036,854,775,808 / 9,223,372,036,854,775,808

Now, what if we need to store a number bigger that this? We can consider using a long or long long but again, what if we want to store a number bigger than a long long?

We will create a new type of number than is no more limited by it size.

Consider now the following program:

// main.cpp

#include <iostream>
#include "infint.hpp"

int main() {
    Infint num = Infint();
    // or Infint num = Infint(0);


    num = num + 1;  // num is equal to "1"
    num += 1;       // num is equal to "2"
    num += "8";       // num is equal to "10"
    num -= "5";     // num is equal to "5"
    num -= num;     // num is equal to "0"


    num = 1;                // num is equal to "1"
    num++;                  // num is equal to "2"
    num = num + num + 1;    // num is equal to "5"
    num--;                  // num is equal to "4"

    std::cout << num << std::endl;
    return 0;
}

Once compiled and executed:

$> ./a.out
$> 4

Our number will have to be stored into a string. If we try to store it into any integer type it will work at the beginning but if we try to insert a number with 2000 digits (ex: 12345[lot of more here]32432432 ) then we will have an overflow.

We will provide 3 constructor:

• Infint::Infint() where the default value is "0"
• Infint::Infint(int)
• Infint::Infint(std::string)

To make it a bit easier, we will only support the following operators

• +
• -
• ++
• --
• +=
• -=
• *
• *=
• =

Our Infint will be included in the -inf <= Infint <= +inf.