error C1004: unexpected end-of-file found in Visual Studio 2012

I want to write a simple C++ code in visual studio 2012 but always getting a error C1004 in the header file. Could anyone please help me?

My code is given below. I am new in visual studio C++, so this may be very silly error.

add.cpp

#include <iostream>

int add(int a, int b)
{
    return a+b;
}

add.h

#ifndef ADD_H
#define ADD_H

int add(int a, int b);

#endif

source.cpp

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

int main()
{
    std::cout << add(3, 4);
    return 0;
}