yeah tampabay was right, you must have a main() function and your return 0; has to be inside of main() Also, you shouldnt use #include <iostream.h> That is bad programming style because it is so old. If your using a very old compiler that is ok, but hopefully you are not. Instead use:
#include <iostream>
using namespace std;
This is better style.
Also i would suggest that you read the little book that teachs you how to use your compiler...i think it will answer a lot of your questions