Q2

Modify the program you wrote in exercise #1 so that readNumber() and writeAnswer() live in a separate file called io.cpp. Use a forward declaration to access them from main().

If you’re having problems, make sure io.cpp is properly added to your project so it gets compiled.

Solution#

main.cpp

int readNumber();
void writeAnswer(int num);

int main()
{
    int x { readNumber() };
    int y { readNumber() };

    writeAnswer(x + y);

    return 0;
}

io.cpp

#include <iostream>

int readNumber()
{
    int num {};

    std::cout << "Enter a number: ";
    std::cin >> num;

    return num;
}

void writeAnswer(int num)
{
    std::cout << "The answer is: " << num << '\n';
}