Print out dates in four formats - c++

Question

I need to print out dates in four formats when a user enters a month, day and year.
For example if I enter "sept" for month, 17 for day and 1921 for year, it will print out:
1) 9/17/1921
2) September 17,1921
3) 1921-9-17
4) 1921-sep-17
I also do validation where if the number of days is less than 1 or greater than than the number of days for that month and the year cannot be less than 1900 or greater than 2020. If it is, month gets defaulted to "January" day to 1 and year to 2001.
When I enter jan for month 5 for day 2005 for year, I get weird values in my console 1/-858993460/-858993460 and then terminates. But when I enter mar 5 2005 i get
3/5/2005
March2005
ory corruption5
ory corruptionmar-5
I create an instance of Date and call a 3 argument constructor. The 3 argument constructor then calls a validate function which return a boolean. If the return value is false, it will call the default constructor which sets everything to january 1 2001.
//UPDATE:
Changed inital value of int index in date.cpp to -1 instead of NULL. Doing this now calls the print function four times four when I enter "jan" but I still get the weird results
1/5/2005
January2005 //This should be January 5, 2005
ory corruption5
ory corruptionmar-5
Why does the first time print is called all my member variables retain the values, but the 2nd, 3rd, and 4th time, day is missing and shows weird corruption message?
I don't know what is going on but when I also enter an invalid date such as "jan" for month but 36 for days and 2025 for year, the default constructor should set month to January, day to 1 and year to 2001 but I get garbage values
1/-858993460/-858993460
This is the first time print is called then after that it terminates.
//Header
#pragma once
#include <iostream>
#include <string>
using namespace std;
/*Add more constants if needed*/
#ifndef DATE_H
#define DATE_H
enum DateFormat { mdy1, mdy2, ymd1, ymd2 };
const int MIN_YEAR = 1900;
const int MAX_YEAR = 2020;
const string monthStr[] = //alternative: const char monthStr[] [15]=
{ "January", "February", "March", "April", "May", "June",
"July", "August", "September", "October", "November",
"December" };
const string monthStrAbbrev[] = //not strictly necessary, but helpful
{ "jan", "feb", "mar", "apr", "may", "jun",
"jul", "aug", "sep", "oct", "nov",
"dec" };
const int monthDays[] =
{ 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
class Date {
private:
string month;
int day, year;
bool validateDate(string, int, int);
Date();
public:
Date(string, int, int);
void print(DateFormat type);
};
#endif // !DATES_H
//Dates.cpp
#include "stdafx.h"
#include <iostream>
#include <algorithm>
#include "date.h"
using std::cout;
using std::cin;
int global;
Date::Date() : month("January"), day(1), year(2001) { cout << "INSIDE CONST" << endl; }
Date::Date(string m, int d, int y)
{
if (!validateDate(m, d, y))
{
cout << "IF FALSE" << endl;
Date();
}
else
{
month = m;
day = d;
year = y;
cout << "MONTH IS :" << month << " DAY IS: " << day << " YEAR IS: " << year << endl;
}
}
bool Date::validateDate(string m, int d, int y)
{
cout << "size is " << sizeof(monthStrAbbrev) / sizeof(monthStrAbbrev[0]) << endl;;
int index = -1;
for (int x = 0; x < 11; x++)
{
string mAbr = monthStr[x].substr (0, 3);
transform(mAbr.begin(), mAbr.end(), mAbr.begin(), (int(*) (int)) tolower);
cout << "Abbr: " << mAbr << endl;
if (m == mAbr)
{
index = x;
global = x;
cout << "x " << x << " global " << global << " Index " << index << endl;
if (d < 1 && d > monthDays[index])
{
cout << "FALSE 1" << endl;
return false;
}
if (y < MIN_YEAR || y > MAX_YEAR)
{
cout << "FALSE 2" << endl;
return false;
}
break;
}
}
if (index == -1)
{
cout << "IF NULL" << endl;
return false;
}
else
{
cout << " IF NOT NULL" << endl;
return true;
}
}
void Date::print(DateFormat type)
{
if (type == mdy1)
{
cout << global + 1 << "/" << day << "/" << year << endl;
}
else if (type == mdy2)
{
cout << monthStr[global] << day + ", " << year << endl;
}
else if (type == ymd1)
{
cout << year + "-" << (global + 1) + "-" << day << endl;
}
else if (type == ymd2)
{
cout << year + "-" << month + "-" << day << endl;
}
}
//Test.cpp
#include "stdafx.h"
#include <iostream>
#include <algorithm>
#include <string>
using namespace std;
#include "date.h"
void setDateValues(string&, int&, int&);
int main()
{
string mth;
int day, yr;
setDateValues(mth, day, yr);
transform(mth.begin(), mth.end(), mth.begin(), (int(*) (int)) tolower);
Date d1(mth, day, yr);
cout << "Date is:\n";
DateFormat type;
type = mdy1;
d1.print(type);
type = mdy2;
d1.print(type);
type = ymd1;
d1.print(type);
type = ymd2;
d1.print(type);
return 0;
}
void setDateValues(string & m, int& d, int& y)
{
cout << "Enter month: ";
cin >> m;
cout << "Enter day: ";
cin >> d;
cout << "Enter year: ";
cin >> y;
}

Answer 1

There is a standard library function for this: strftime().
You give it a date in a struct, and it writes a string. For your four cases, the format strings would be:
1) %m/%d/%Y
2) %B %d, %Y
3) %F
4) %Y-%b-%d