It looks like your old source uses old C++ (pre-ISO 14882 standard) header files. It probably also does not use compliant namespaces.
Change the header files to compliant ones (e.g., #include <iostream.h> becomes #include <iostream>).
And add in std:: by either "std::ID"prefix in front of each standard namespace identifier (metasyntactically given here as "ID"), or "using std::ID" near the top of the source file, or just carte blanche by "using namespace std;" after the #include specifier block near the top of the source code.
You might also want to change the ".c" extension to ".cpp".
HTH, --Eljay
