I am a beginning programmer, with almost no knowledge whatsoever. I am trying to make a very simple program with one header file, just to test out the principle. However, I cannot seem to get it to work. Whenever I try to compile, I get this error:

in header file, 'string' does not have a type
invalid conversion from 'const char*' to 'int'

Here is my source code:

//MULTIFILE.CPP (source file)
#include <iostream>
#include <string>
#include "Multifile.h"
using namespace std;
int main()
{
cout << "Tripling 9: " << times3(9) << endl;
cout << "Tripling 'game': " << times3("hello") << "\n\n";
return 0;
}

//MULTIFILE.H (header file)
#ifndef MULTIFILE_H
#define MULTIFILE_H
int times3(int number) { return (number * 3); }
string times3(string text) { return (text + text + text); }
#endif

I have tried different "using" and std::string things in both the source and header, tried #including string in the header, and nothing seems to work... I keep getting the error. It does not seem to have anything to do with function overloading, and I am stuck.

Please help!