The problem is in dayOfWeek () I think. It may be overloaded or something.

#ifndef DATE_H
#define DATE_H

class Date 
{
public:
   Date( int = 1, int = 1, int = 1900 ); // default constructor
   void print() const; // print date in month/day/year format
   int dayOfWeek (); // This one returns the day of the week from the current m/d/y
  // ~Date(); // provided to confirm destruction order
  
private:
   int month; // 1-12 (January-December)
   int day; // 1-31 based on month
   int year; // any year

   // utility function to check if day is proper for month and year
   int checkDay( int ) const; 
}; // end class Date

#endif


// Fig. 11.11: Date.cpp
// Date class member-function definitions.
#include <iostream>
using std::cout;
using std::endl;

//#include "Date.h" // include Date class definition

// constructor confirms proper value for month; calls
// utility function checkDay to confirm proper value for day
Date::Date( int mn, int dy, int yr )
{
   if ( mn > 0 && mn <= 12 ) // validate the month
      month = mn;
   else 
   {                     
      month = 1; // invalid month set to 1
      cout << "Invalid month (" << mn << ") set to 1.\n";
   } // end else

   year = yr; // could validate yr
   day = checkDay( dy ); // validate the day

   // output Date object to show when its constructor is called
 //  cout << "Date object constructor for date ";
   print();                   
   cout << endl;
} // end Date constructor

// print Date object in form month/day/year
void Date::print() const
{
   cout << month << '/' << day << '/' << year; 
} // end function print

// output Date object to show when its destructor is called
/*
Date::~Date()
{ 
   cout << "Date object destructor for date ";
   print();
   cout << endl;
} // end ~Date destructor
*/
// utility function to confirm proper day value based on 
// month and year; handles leap years, too

int Date::dayOfWeek ()
{
/* We use the formula below where floor() denotes the integer floor function,
W = (k + floor(2.6m - 0.2) - 2C + Y + floor(Y/4) + floor(C/4)) mod 7 
k is day (1 to 31)
m is month (1 = March, ..., 10 = December, 11 = Jan, 12 = Feb) Treat Jan & Feb as months of the preceding year
C is century (1987 has C = 19)
Y is year (1987 has Y = 87 except Y = 86 for Jan & Feb)
W is week day (0 = Sunday, ..., 6 = Saturday)
from the website
http://www.mcs.csueastbay.edu/~malek/Mathlinks/Weekdays.html 
*/
int k, m, C, Y, W;

m = month - 2;  // Fix m to start from 1 for march
if (m <=0)
   m += 12;

k = day; // 
C = year / 100;
Y = year % 100;

if (m >= 11)
   Y = Y -1;      // Adjust for January and Febrarury

W = (k + (int)(2.6*m - 0.2) - 2*C + Y + Y/4 + C/4) % 7  ;

return W;


}
int Date::checkDay( int testDay ) const
{
   static const int daysPerMonth[ 13 ] = 
      { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };

   // determine whether testDay is valid for specified month
   if ( testDay > 0 && testDay <= daysPerMonth[ month ] )
      return testDay;

   // February 29 check for leap year 
   if ( month == 2 && testDay == 29 && ( year % 400 == 0 || 
      ( year % 4 == 0 && year % 100 != 0 ) ) )
      return testDay;

   cout << "Invalid day (" << testDay << ") set to 1.\n";
   return 1; // leave object in consistent state if bad value
} // end function checkDay

#include <iostream>
//#include "Date.h"
using namespace std;
int main () {
	 char  *DOW [8] = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday",
		"Saturday"};
	Date d(7,1,2010);
	d.print();
    int x = d.dayOfWeek();

	cout << "Day of week for 11/2/2009 is " << DOW[x] << endl;
}

thats a long code now still analyzing

Huh? Would take about 30 seconds to get that "working". Bad code is bad, bad questions are worse and asking other people to do their work for them should be a ban-able offence.