Program to find any day of the week | C ++

#include <iostream>
#include <cmath> // for floor()
#include <conio.h> // for getch()
#include <stdlib.h> // for exit()
#include <windows.h> // for system()
using std::cout;
using std::cin;
//=======================
void Menu( void );
int main( void )
{
Menu();
return 0;
}// End of main function
//=======================
void Menu( void )
{
int year, month, day;
int week;
int century;
int temp;
bool flag= false;
system( “cls” );
cout<< “\n\n =========== Calculate any day of the week =========== “;
cout<< “\n\n\t\t Enter year month day: “;
cin>> year>> month>> day;
temp= year;
if( year<= 1582 && month<= 10 && day<= 15 )
{
flag= true;
}
if( month== 2 || month== 1 )
{
year–;
month= 12+ month;
}
century= year/ 100;
year= year% 100; // The last two digits of the year
if( flag== false )
{
week= year+ ( int )floor( ( double )year/ 4 )+ ( int )floor( ( double )century/ 4 )- 2* century+
( int )floor( (double ) 26*( month+ 1 )/ 10 )+ day- 1;
}
else
{
week= year+ ( int )floor( ( double )year/ 4 )+ ( int )floor( ( double )century/ 4 )- 2* century+
( int )floor( ( double ) 26*( month+ 1 )/ 10 )+ day- 3;
}
week= ( week% 7+ 7 )% 7;
year= temp;
switch( week )
{
case 0:
{
cout<< “\n\n\t\t “;
cout<< year<< “-“<< month<< “-“<< day<< “: “<< “Sunday”;
break;
}
case 1:
{
cout<< “\n\n\t\t “;
cout<< year<< “-“<< month<< “-“<< day<< “: “<< “Monday”;
break;
}
case 2:
{
cout<< “\n\n\t\t “;
cout<< year<< “-“<< month<< “-“<< day<< “: “<< “Tuesday”;
break;
}
case 3:
{
cout<< “\n\n\t\t “;
cout<< year<< “-“<< month<< “-“<< day<< “: “<< “Wednesday”;
break;
}
case 4:
{
cout<< “\n\n\t\t “;
cout<< year<< “-“<< month<< “-“<< day<< “: “<< “Thursday”;
break;
}
case 5:
{
cout<< “\n\n\t\t “;
cout<< year<< “-“<< month<< “-“<< day<< “: “<< “Friday”;
break;
}
case 6:
{
cout<< “\n\n\t\t “;
cout<< year<< “-“<< month<< “-“<< day<< “: “<< “Saturday”;
break;
}
}
cout<< “\n\n\t\t Do you want to continue( Y/N ): “;
char letter;
cin>>letter;
if( toupper( letter)== ‘Y’ )
{
Menu();
}
else
{
cout<< “\n\n\t\t Thank U.”;
getch();
exit( 1 );
}
}// End of Menu function