diff --git a/feladat3/IFPQYY_feladat3V1/IFPQYY_feladat3V1.zip b/feladat3/IFPQYY_feladat3V1/IFPQYY_feladat3V1.zip
deleted file mode 100644
index abac7ed..0000000
Binary files a/feladat3/IFPQYY_feladat3V1/IFPQYY_feladat3V1.zip and /dev/null differ
diff --git a/feladat4/feladat4/cmydate.cpp b/feladat4/feladat4/cmydate.cpp
index ee4eadf..f1da396 100644
--- a/feladat4/feladat4/cmydate.cpp
+++ b/feladat4/feladat4/cmydate.cpp
@@ -1,81 +1,40 @@
-//Tóth Dániel Mátyás | IFPQYY | V1
+//Tóth Dániel Mátyás | IFPQYY | V1
 #include <iostream>
 #include "cmydateexception.h"
 #include "cmydate.h"
+#define TIMESTAMP_YEAR 1970
 using namespace std;
 
-static bool IsLeapYear(int year) {
-	if (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0))
-	{
-		return true;
-	}
-	return false;
-}
-static bool IsValidYear(int year) {
-	if (year < 1970)
-	{
-		throw new CMyDateException(CMyDateException::ErrMinYear);
-	}
-	return true;
-}
-static bool IsValidMonth(int month) {
-	if (month < 1)
-	{
-		throw new CMyDateException(CMyDateException::ErrMinMonth);
-	}
-	if (month > 12)
-	{
-		throw new CMyDateException(CMyDateException::ErrMaxMonth);
-	}
-	return true;
-}
-static bool IsValidDay(int year, int month, int day) {
-	if (day < 1)
-	{
-		throw new CMyDateException(CMyDateException::ErrMinDay);
-	}
-	switch (month)
-	{
-	case 1:
-	case 3:
-	case 5:
-	case 7:
-	case 8:
-	case 10:
-	case 12:
-		if (day > 31)
-		{
-			throw new CMyDateException(CMyDateException::ErrMaxDay);
-		}
-		break;
-	case 4:
-	case 6:
-	case 9:
-	case 11:
-		if (day > 30)
-		{
-			throw new CMyDateException(CMyDateException::ErrMaxDay);
-		}
-		break;
-	case 2:
-		if (day > 29 || (day > 28 && !IsLeapYear(year)))
-		{
-			throw new CMyDateException(CMyDateException::ErrMaxDay);
-		}
-		break;
-	default:
-		throw new CMyDateException(CMyDateException::ErrUnexpected);
-		break;
-	}
-}
+static char monthnames[12][11] = {
+	"Január",
+	"Február",
+	"Március",
+	"Április",
+	"Május",
+	"Június",
+	"Július",
+	"Augusztus",
+	"Szeptember",
+	"Október",
+	"November",
+	"December"
+};
+
+static bool IsLeapYear(int year);
+static int GetMonthDayCount(int month, int year);
+static bool IsValidYear(int year);
+static bool IsValidMonth(int month);
+static bool IsValidDay(int year, int month, int day);
+static int DateToTimeStamp(int year, int month, int day);
+static void TimeStampToDate(int timestamp, int* year, int* month, int* day);
+static int DayOfTheYearArgs(int year, int month, int day);
 
 CMyDate::CMyDate() {
-	m_iYear = 1970;
-	m_iMonth = 1;
-	m_iDay = 1;
+	SetYear(1970);
+	SetMonth(1);
+	SetDay(1);
 }
 CMyDate::CMyDate(int year, int month, int day) {
-	IsValid(year, month, day);
 	SetYear(year);
 	SetMonth(month);
 	SetDay(day);
@@ -84,75 +43,53 @@ CMyDate::~CMyDate(){
 	//hey jimmy, get me a destructor with nothing
 }
 void CMyDate::Display() const {
-	char monthName[11] = {};
-	switch (m_iMonth)
-	{
-	case 1:
-		strncpy(monthName, "Január", 7);
-		break;
-	case 2:
-		strncpy(monthName, "Február", 8);
-		break;
-	case 3:
-		strncpy(monthName, "Március", 8);
-		break;
-	case 4:
-		strncpy(monthName, "Április", 9);
-		break;
-	case 5:
-		strncpy(monthName, "Május", 6);
-		break;
-	case 6:
-		strncpy(monthName, "Június", 7);
-		break;
-	case 7:
-		strncpy(monthName, "Július", 7);
-		break;
-	case 8:
-		strncpy(monthName, "Augusztus", 10);
-		break;
-	case 9:
-		strncpy(monthName, "Szeptember", 11);
-		break;
-	case 10:
-		strncpy(monthName, "Október", 8);
-		break;
-	case 11:
-		strncpy(monthName, "November", 9);
-		break;
-	case 12:
-		strncpy(monthName, "December", 9);
-		break;
-	default:
-		throw new CMyDateException(CMyDateException::ErrUnexpected);
-		break;
-	}
-	cout << m_iYear << " " << monthName << " " << m_iDay << ".";
+	cout << GetYear() << " " << monthnames[GetMonth() - 1] << " " << GetDay() << ".";
 }
 int CMyDate::DayOfTheYear() const {
-	int d = 30.4375 * (m_iMonth - 1); //avg day in a month
-	return d + m_iDay - (int)IsLeapYear(m_iYear);
+	return DayOfTheYearArgs(GetYear(), GetMonth(), GetDay());
 }
 bool CMyDate::IsValid(int year, int month, int day) const {
-	try
-	{
-		IsValidYear(year);
-		IsValidMonth(month);
-		IsValidDay(year, month, day);
-	}
-	catch (const CMyDateException& e)
-	{
-		
-	}
+	IsValidYear(year);
+	IsValidMonth(month);
+	IsValidDay(year, month, day);
 	return true;
 }
 void CMyDate::AddDays(int days) {
+	int timestamp = DateToTimeStamp(GetYear(), GetMonth(), GetDay());
+	int y = 0, m = 0, d = 0;
+	TimeStampToDate(timestamp + days, &y, &m, &d);
+	IsValid(y, m, d);
+	m_iYear = y;
+	m_iMonth = m;
+	m_iDay = d;
 }
-int CMyDate::SubDays(int days) {
+void CMyDate::SubDays(int days) {
+	AddDays(days * (-1));
 }
 int CMyDate::DifferenceInDays(const CMyDate& other) const {
+	int thistmstmp = DateToTimeStamp(GetYear(), GetMonth(), GetDay());
+	int othertmstmp = DateToTimeStamp(other.GetYear(), other.GetMonth(), other.GetDay());
+	int result = thistmstmp - othertmstmp;
+	return result < 0 ? result * (-1) : result;
 }
 void CMyDate::AddMonths(int months) {
+	m_iYear += (m_iMonth - 1 + months) / 12;
+	m_iMonth += ((m_iMonth - 1 + months) % 12) + 1;
+	try
+	{
+		IsValidDay(m_iYear, m_iMonth, m_iDay);
+	}
+	catch (CMyDateException e)
+	{
+		if (e.what() == CMyDateException::ErrMaxDay)
+		{
+			SetDay(GetMonthDayCount(m_iMonth, m_iYear));
+		}
+		else
+		{
+			throw e;
+		}
+	}
 }
 int CMyDate::GetDay() const {
 	return m_iDay;
@@ -181,3 +118,117 @@ void CMyDate::SetYear(int year) {
 		m_iYear = year;
 	}
 }
+
+static bool IsLeapYear(int year) {
+	if (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0))
+	{
+		return true;
+	}
+	return false;
+}
+static int GetMonthDayCount(int month, int year) {
+	IsValidMonth(month);
+	switch (month)
+	{
+	case 1:
+	case 3:
+	case 5:
+	case 7:
+	case 8:
+	case 10:
+	case 12:
+		return 31;
+		break;
+	case 4:
+	case 6:
+	case 9:
+	case 11:
+		return 30;
+		break;
+	case 2:
+		if (IsLeapYear(year))
+		{
+			return 29;
+		}
+		else
+		{
+			return 28;
+		}
+		break;
+	default:
+		throw new CMyDateException(CMyDateException::ErrUnexpected);
+		break;
+	}
+}
+static bool IsValidYear(int year) {
+	if (year < 1970)
+	{
+		throw new CMyDateException(CMyDateException::ErrMinYear);
+	}
+	return true;
+}
+static bool IsValidMonth(int month) {
+	if (month < 1)
+	{
+		throw new CMyDateException(CMyDateException::ErrMinMonth);
+	}
+	if (month > 12)
+	{
+		throw new CMyDateException(CMyDateException::ErrMaxMonth);
+	}
+	return true;
+}
+static bool IsValidDay(int year, int month, int day) {
+	int monthday = GetMonthDayCount(month, year);
+	if (day < 1)
+	{
+		throw new CMyDateException(CMyDateException::ErrMinDay);
+	}
+	if (day > monthday)
+	{
+		throw new CMyDateException(CMyDateException::ErrMaxDay);
+	}
+	return true;
+}
+static int DateToTimeStamp(int year, int month, int day) { //counting from 1970-01-01
+	int y = year - 1;
+	int e = TIMESTAMP_YEAR - 1;
+
+	int days = 365 * (year - TIMESTAMP_YEAR)
+		+ (y / 4 - e / 4)
+		- (y / 100 - e / 100)
+		+ (y / 400 - e / 400);
+
+	return days + DayOfTheYearArgs(year, month, day - 1);
+}
+static void TimeStampToDate(int timestamp, int* year, int* month, int* day) {
+	*year = TIMESTAMP_YEAR;
+	while (timestamp < 0)
+	{
+		(*year)--;
+		timestamp += IsLeapYear(*year) ? 366 : 365;
+	}
+	while (timestamp >= (IsLeapYear(*year) ? 366 : 365))
+	{
+		timestamp -= IsLeapYear(*year) ? 366 : 365;
+		(*year)++;
+	}
+
+	*month = 1;
+	int monthDay = GetMonthDayCount(*month, *year);
+	while (timestamp >= monthDay)
+	{
+		timestamp -= monthDay;
+		(*month)++;
+		monthDay = GetMonthDayCount(*month, *year);
+	}
+
+	*day = timestamp + 1;
+}
+static int DayOfTheYearArgs(int year, int month, int day) {
+	for (size_t i = 1; i < month; i++)
+	{
+		day += GetMonthDayCount(i, year);
+	}
+	return day;
+}
\ No newline at end of file
diff --git a/feladat4/feladat4/cmydate.h b/feladat4/feladat4/cmydate.h
index 90c090d..ba7e6df 100644
--- a/feladat4/feladat4/cmydate.h
+++ b/feladat4/feladat4/cmydate.h
@@ -1,4 +1,4 @@
-//Tóth Dániel Mátyás | IFPQYY | V1
+//Tóth Dániel Mátyás | IFPQYY | V1
 #pragma once
 class CMyDate {
 public:
@@ -9,7 +9,7 @@ public:
 	int DayOfTheYear() const;
 	bool IsValid(int year, int month, int day) const;
 	void AddDays(int days);
-	int SubDays(int days);
+	void SubDays(int days);
 	int DifferenceInDays(const CMyDate& other) const;
 	void AddMonths(int months);
 	int GetDay() const;
diff --git a/feladat4/feladat4/cmydateexception.cpp b/feladat4/feladat4/cmydateexception.cpp
index 6755035..75b06ff 100644
--- a/feladat4/feladat4/cmydateexception.cpp
+++ b/feladat4/feladat4/cmydateexception.cpp
@@ -1,8 +1,30 @@
-//Tóth Dániel Mátyás | IFPQYY | V1
+//Tóth Dániel Mátyás | IFPQYY | V1
 #include "cmydateexception.h"
-#include <iostream>
+
+static int CopyStr(char* dest, const char* src, const char* concat = "\0") {
+	if (dest == nullptr || src == nullptr) {
+		return -1;
+	}
+	int i = 0;
+	while (src[i] != '\0')
+	{
+		dest[i++] = src[i];
+	}
+	int j = 0;
+	while (concat[j] != '\0')
+	{
+		dest[i++] = concat[j++];
+	}
+	dest[i] = '\0';
+	return -1;
+}
 
 CMyDateException::CMyDateException(const char* s)
 {
-	strncpy(msg, s, sizeof(s));
+	CopyStr(msg, s);
 }
+
+const char* CMyDateException::what() {
+	return msg;
+}
+
diff --git a/feladat4/feladat4/cmydateexception.h b/feladat4/feladat4/cmydateexception.h
index 29c1739..3e834f2 100644
--- a/feladat4/feladat4/cmydateexception.h
+++ b/feladat4/feladat4/cmydateexception.h
@@ -1,14 +1,15 @@
-//Tóth Dániel Mátyás | IFPQYY | V1
+//Tóth Dániel Mátyás | IFPQYY | V1
 #pragma once
 class CMyDateException {
 public:
 	CMyDateException(const char* s);
+	const char* what(void);
 	static constexpr const char* ErrMinDay = "Hiba: nap kisebb, mint 1!";
-	static constexpr const char* ErrMaxDay = "Hiba: nap nagyobb, mint az adott hónap napszáma!";
-	static constexpr const char* ErrMinMonth = "Hiba: hónap kisebb, mint 1!";
-	static constexpr const char* ErrMaxMonth = "Hiba: hónap nagyobb, mint 12!";
-	static constexpr const char* ErrMinYear = "Hiba: év kisebb, mint 1970!";
-	static constexpr const char* ErrUnexpected = "Váratlan hiba";
+	static constexpr const char* ErrMaxDay = "Hiba: nap nagyobb, mint az adott honap napszama!";
+	static constexpr const char* ErrMinMonth = "Hiba: honap kisebb, mint 1!";
+	static constexpr const char* ErrMaxMonth = "Hiba: honap nagyobb, mint 12!";
+	static constexpr const char* ErrMinYear = "Hiba: ev kisebb, mint 1970!";
+	static constexpr const char* ErrUnexpected = "Varatlan hiba";
 private:
 	char* msg;
 };
\ No newline at end of file
diff --git a/feladat4/feladat4/feladat4.vcxproj b/feladat4/feladat4/feladat4.vcxproj
index 37436df..1077ca5 100644
--- a/feladat4/feladat4/feladat4.vcxproj
+++ b/feladat4/feladat4/feladat4.vcxproj
@@ -111,6 +111,7 @@
       <PreprocessorDefinitions>_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <ConformanceMode>true</ConformanceMode>
       <LanguageStandard>stdcpp20</LanguageStandard>
+      <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>
       <SubSystem>Console</SubSystem>
diff --git a/feladat4/feladat4/main.cpp b/feladat4/feladat4/main.cpp
index bdf6b87..9caaa8b 100644
--- a/feladat4/feladat4/main.cpp
+++ b/feladat4/feladat4/main.cpp
@@ -1,6 +1,95 @@
 //Tóth Dániel Mátyás | IFPQYY | V1
-#include "feladat4.h"
+#include "cmydate.h"
+using namespace std;
+/*#define TIMESTAMP_YEAR 1970
+static bool IsLeapYear(int year) {
+	if (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0))
+	{
+		return true;
+	}
+	return false;
+}
+static int GetMonthDayCount(int month, int year) {
+	switch (month)
+	{
+	case 1:
+	case 3:
+	case 5:
+	case 7:
+	case 8:
+	case 10:
+	case 12:
+		return 31;
+		break;
+	case 4:
+	case 6:
+	case 9:
+	case 11:
+		return 30;
+		break;
+	case 2:
+		if (IsLeapYear(year))
+		{
+			return 29;
+		}
+		else
+		{
+			return 28;
+		}
+		break;
+	default:
+		throw new CMyDateException(CMyDateException::ErrUnexpected);
+		break;
+	}
+}
+static int DayOfTheYearArgs(int year, int month, int day) {
+	for (int i = 1; i < month; i++)
+	{
+		day += GetMonthDayCount(i, year);
+	}
+	return day;
+}
+static int DateToTimeStamp(int year, int month, int day) { //counting from 1970-01-01
+	int y = year - 1;
+	int e = TIMESTAMP_YEAR - 1;
+
+	int days = 365 * (year - TIMESTAMP_YEAR)
+		+ (y / 4 - e / 4)
+		- (y / 100 - e / 100)
+		+ (y / 400 - e / 400);
+
+	return days + DayOfTheYearArgs(year, month, day - 1);
+}
+static void TimeStampToDate(int timestamp, int* year, int* month, int* day) {
+	*year = TIMESTAMP_YEAR;
+	while (timestamp < 0)
+	{
+		(*year)--;
+		timestamp += IsLeapYear(*year) ? 366 : 365;
+	}
+	while (timestamp >= (IsLeapYear(*year) ? 366 : 365))
+	{
+		timestamp -= IsLeapYear(*year) ? 366 : 365;
+		(*year)++;
+	}
+
+	*month = 1;
+	int monthDay = GetMonthDayCount(*month, *year);
+	while (timestamp >= monthDay)
+	{
+		timestamp -= monthDay;
+		(*month)++;
+		monthDay = GetMonthDayCount(*month, *year);
+	}
+
+	*day = timestamp + 1;
+}*/
 
 int main() {
+	/*int t = DateToTimeStamp(1976, 10, 23);
+	cout << t << "\n";
+	int y = 0, m = 0, d = 0;
+	TimeStampToDate(t, &y, &m, &d);
+	cout << y << ". " << m << ". " << d << ".";*/
 	return 0;
 }
\ No newline at end of file