fstream/datafile problem

Perhaps someone can help me here. I have been looking over this code and I cannot figure why it is giving me an error(s). If someone can give me an alternative way I would greatly appreciate it.

The program is not entirely finished. The program is basically about classes which reads and writes into a datafile (pa8.dat).

Code:

#include <string>
#include <vector>
#include <iostream.h>
#include <iomanip.h>
#include <stdio.h>
#include <fstream.h>
#include <stdlib.h>



/**********************************base class REObject*******************/
class REObject
{
public:
  int block; //location var
  int lot; //location var
  float price; //price var
  int sq_footage; //duh

  virtual void Print(); //overridden in subclasses
  virtual void Write(); //overridden in subclasses

private:
};

//member methods - to be overridden!
void REObject::Print() {cout<<"print REObject"<<endl;}
void REObject::Write() {cout<<"write REObject"<<endl;}

/**************** ONE FAMILYderived from REObject ***********************/
class OneFamily : public REObject
{
public:
  void Print(); //overridden
  void Write(); //overridden
private:
  int bathrooms;
  int baths;
  int year_built;
};

//member methods
void OneFamily::Print() {cout<<"print OneFamily"<<endl;}
void OneFamily::Write() {cout<<"write OneFamily"<<endl;}


/**************** COMMERCIAL derived from REObject *************************/
class Commercial : public REObject
{
public:
  void Print(); //overridden
  void Write(); //overridden
private:
  char type_of_commerce;
  bool sub_dividable;
};

//member methods
void Commercial::Print() {cout<<"print Commercial"<<endl;}
void Commercial::Write() {cout<<"write Commercial"<<endl;}


/***************** MULTIPLE DWEELING derived from REObject *******************/
class MultipleDwelling : public REObject
{
public:
  void Print(); //overridden
  void Write(); //overridden
private:
  int num_of_units;
};

//member methods
void MultipleDwelling::Print() {cout<<"print MultipleDwelling"<<endl;}
void MultipleDwelling::Write() {cout<<"write MultipleDwelling"<<endl;}

/******************** REDBASE ************************/
class REDbase
{
public:
  REDbase(char *file); //constructor: get filename from th CLI, opens the file, 
                       //builds the dbase in an array of pointers...
  ~REDbase(); //destructor: writes the dbase back to file...
  void Add();
  void Print();
  void Save();
private:
  //vector<REObject*> dbase; //an array of REObject pointers (our database)
  REObject* dbase[100]; //array of pointers to REobjects 
  char DataFile[50]; //data file name 
};

REDbase::REDbase(char *file)
{
  ifstream ifdatafile;
  
  ifdatafile.open(file); 
  if(!ifdatafile)
    {
      cout<<"Couldn't open dictionary. Exiting..."<<endl;
      exit(1);
    }
  
  string word;
 
  while(ifdatafile>>word)
    {
      //parse the datafile
      if(!strcmp(word.c_str(),"s"))
	{
	  cout<<endl;
	  cout<<"single dwelling: ";
	  new OneFamily;
	}
      else if(!strcmp(word.c_str(),"m"))
	{
	  cout<<endl;
	  cout<<"multi dwelling :";
	  new MultipleDwelling;
	}
      else if(!strcmp(word.c_str(), "c"))
	{
	  cout<<endl;
	  cout<<"commercial :";
	  new Commercial;
	}
      else { cout<<" "<<word<<" "; }
    }
  cout<<endl;
}


/*******************************MAIN************************************************/

int main(int argc, char ** argv)
{
  /* main calls class REObject member function constructor to open data file, parse the data
     and populate the database, filename is static! */

  new REDbase("pa8.dat");

  /* main the enters a UI loop, giving the option to add a listing, print all listings
     to the console, or saving the dbase to a file and then quitting the program. 
     main determines the input and then calls member functions of REDbase accordingly */

  return (0);
}

The Error Message

Code:

--------------------Configuration: pa8 - Win32 Debug--------------------
Compiling...
pa8.cpp
c:\documents and settings\val\desktop\c++\pa8.cpp(102) : error C2065: 'string' : undeclared identifier
c:\documents and settings\val\desktop\c++\pa8.cpp(102) : error C2146: syntax error : missing ';' before identifier 'word'
c:\documents and settings\val\desktop\c++\pa8.cpp(102) : error C2065: 'word' : undeclared identifier
c:\documents and settings\val\desktop\c++\pa8.cpp(107) : error C2228: left of '.c_str' must have class/struct/union type
c:\documents and settings\val\desktop\c++\pa8.cpp(113) : error C2228: left of '.c_str' must have class/struct/union type
c:\documents and settings\val\desktop\c++\pa8.cpp(119) : error C2228: left of '.c_str' must have class/struct/union type
Error executing cl.exe.

pa8.obj - 6 error(s), 0 warning(s)

P.S I am using Visual C++ as the compiler.


Thanks.

couple of those errors can be fixed by adding [code]using namespace std;[/quote]after your includes

Already tried that, and gives me theres errors.

Code:

Compiling...
pa8.cpp
c:\documents and settings\val\desktop\c++\pa8.cpp(95) : error C2872: 'ifstream' : ambiguous symbol
c:\documents and settings\val\desktop\c++\pa8.cpp(106) : error C2679: binary '>>' : no operator defined which takes a right-hand operand of type 'class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >' (or there is 
no acceptable conversion)
c:\documents and settings\val\desktop\c++\pa8.cpp(106) : fatal error C1903: unable to recover from previous error(s); stopping compilation
Error executing cl.exe.

pa8.obj - 3 error(s), 0 warning(s)

If I just do #include<fstream>
I get this error.

Code:

--------------------Configuration: pa8 - Win32 Debug--------------------
Compiling...
pa8.cpp
c:\documents and settings\val\desktop\c++\pa8.cpp(127) : error C2679: binary '<<' : no operator defined which takes a right-hand operand of type 'class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >' (or there is 
no acceptable conversion)
Error executing cl.exe.

pa8.obj - 1 error(s), 0 warning(s)