How to Calculate Tomorrow's date, when leap years don't matter

[arooj]

I'm trying to make a program to calculate tomorrow's date, but I've come across some problems. Leap years don't matter, February always has 28 days. A loop must be used.


Class

//MydateClass.h – MyDate class definition

#include <iostream>

using std::cout;
using std::endl;

//declaration section
class MyDate
{
public:
	MyDate();
	void SetDate(int, int, int);
	void DisplayDate();
	void UpdateDate();
private:
	int month;
	int day;
	int year;
};

//implementation section
MyDate::MyDate()
{
	month = 0;
	day   = 0;
	year  = 0;
} //end of default constructor

void MyDate::SetDate(int n1,int n2, int n3)
{
	month = n1;
	day   = n2;
	year  = n3;
} //end of SetDate method

void MyDate::DisplayDate()
{
	cout << month << "/" << day << "/" << year;
} //end of DisplayDate method

void MyDate::UpdateDate()
{
	if (day = 31; && (month = 1; || month = 3; || month = 5; || month = 7; || month = 8; || month = 10; || month = 12))
	{
		if (month = 12)
		{
			day = 1;
			year = year + 1;
		}
		else 
		{
		day = 1;
		month = month + 1;
		}
	}
	if (day = 30 && (month = 4|| month = 6 || month = 9 || month = 11))
	{
		day = 1;
		month = month + 1;
	}
	if (day = 28 && month = 2)
	{
		day = 1;
		month = month + 1;
	}
	else
	{
		day = day + 1;
} //end of UpdateDate method 

Main

//Date.cpp – displays an item name and a quantity in inventory

#include <iostream>
#include "c:\Users\Documents\Visual Studio 2008\Projects\Date solution\Date\MydateClass.h"

using std::cout;
using std::cin;
using std::endl;

int main()
{
	//declare a date object
	MyDate today;

	//declare variables
	int todayMonth = 0;
	int todayDay   = 0;
	int todayYear  = 0;

	//get month,day, and year from user
	cout << "Enter the month (1-12): ";
	cin >> todayMonth;
	cout << "Enter the day (1-31): ";
	cin >> todayDay;
	cout << "Enter the year: ";
	cin >> todayYear;

	//use public member method to assign values to private data members
	today.SetDate(todayMonth, todayDay, todayYear);

	//use public member method to display values in private data members
	cout << endl << "Today is ";
	today.DisplayDate();
	cout << "." << endl;

	today.UpdateDate();
	cout << "Tomorrow is ";
	today.DisplayDate();
	cout << "." << endl;

	return 0;
} //end of main function 

I have multiple errors when I do this, but I don't see how else to do the problem. I also do not know where to incorporate a loop.

[Eyad]

//declaration section
class MyDate
{
public:
	MyDate();//default constructor
	MyDate(int, int, int);// overloading constructor
	void DisplayDate();
	void UpdateDate();
private:
	int month;
	int day;
	int year;
};

MyDate::MyDate(int n1,int n2, int n3)
{
	month = n1;
	day   = n2;
	year  = n3;
}

[cire]

	if (day = 31; && (month = 1; || month = 3; || month = 5; || month = 7; || month = 8; || month = 10; || month = 12))
// should be:
	if (day == 31 && (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12))

Note the use of == and the lack of semi-colons. == is comparison. = is assignment.

Don't forget to update the other if() statements!

[arooj]

I was told to incorporate a loop into the program, and this would make it more efficient. How would I do this?

Date class (Where the errors were)

//MydateClass.h – MyDate class definition

#include <iostream>

using std::cout;
using std::endl;

//declaration section
class MyDate
{
public:
	MyDate();
	void SetDate(int, int, int);
	void DisplayDate();
	void UpdateDate();
private:
	int month;
	int day;
	int year;
};

//implementation section
MyDate::MyDate()
{
	month = 0;
	day   = 0;
	year  = 0;
} //end of default constructor

void MyDate::SetDate(int n1,int n2, int n3)
{
	month = n1;
	day   = n2;
	year  = n3;
} //end of SetDate method

void MyDate::DisplayDate()
{
	cout << month << "/" << day << "/" << year;
} //end of DisplayDate method

void MyDate::UpdateDate()
{
	if (day == 31 && (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12))
	{
		if (month == 12)
		{
			month = 1;
			day = 0;
			year = year + 1;
		}
		else 
		{
		day = 0;
		month = month + 1;
		}
	}
	if (day == 30 && (month == 4|| month == 6 || month == 9 || month == 11))
	{
		day = 0;
		month = month + 1;
	}
	if (day == 28 && month == 2)
	{
		day = 1;
		month = month + 1;
	}
	else
	{
		day = day + 1;
	}
} //end of UpdateDate method