cout is not a member of std

Question

I'm practicing using mulitple files and header files etc. So I have this project which takes two numbers and then adds them. Pretty simple.

Here are my files:

main.cpp

#include <iostream>
#include "add.h"

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

    writeAnswer(x + y);

    return(0);
}

io.cpp

int readNumber()
{
    int x;

    std::cout << "Number: ";
    std::cin >> x;

    return x;
}

void writeAnswer(int x)
{
    std::cout << "Answer: ";
    std::cout << x;
}

add.h

#ifndef ADD_H_INCLUDED
#define ADD_H_INCLUDED

int readNumber();
void writeAnswer(int x);

#endif // #ifndef ADD_H_INCLUDED

The error is showing up in io.cpp. The exact errors are:

Does anyone have any idea why this may be happening? Thanks.

EDIT: I made a small project yesterday with the same amount of files (2 .cpp and 1.h) and I didn't include the iostream header in the other .cpp and it still compiled and ran fine.

Re your edit: then you compiled that project differently. Including iostream in your second cpp file is required as you have it here. Maybe you had that include in the .h file last time around. — Mat
Yeah, it's working great now, thanks for the quick responses everyone! :) — Paul Hannon

unkulunkulu unkulunkulu · Accepted Answer · 2012-07-07T14:45:29

378

votes

add #include <iostream> to the start of io.cpp too.

cout is not a member of std

3 Answers