Respuesta :
#include<iostream>
#include<string>
usingnamespace std;
void menu(); //declartion of function to show the menu
classdayType//creating the class
{
   string Wdays[7];
   int i;
   string day;
   string prDay;
   string NxtDay;
   string AddDays;
public:
   dayType(string);//constructor with one parameter
   string setday(); //declartion of function to set the day
   string preday(); // declartion of function to find privious day
   void Nextday(); // declartion of function to find Next day
   string add(int n); // declartion of function to find after addingthenumber of days given by the user
   void print(); // declartion of function to print the result
};
int main()
{
   int n;
   string d;
   menu(); //displaying menu
   cout <<"Enter the day :";
   getline(cin, d); //Takes the day from the user
   dayType Da(d); //creating an object of a class
   Da.setday();
   Da.preday();
   Da.Nextday();
   cout <<"Enter the No. of days to add :";
   while (!(cin >> n) ||n<0) { //validation checking
          cin.clear();
          cin.ignore(999, '\n');
          cout <<"Invalid data type! \nPlease enter No. of daysto add again :";
      Â
   }
   Da.add(n);
   Da.print();
   system("pause");
   return 0;
}
dayType::dayType(stringi) :day(i){ //Defintion of a constructor with one parameter
   Wdays[0] = "Mon";
   Wdays[1] = "Tues";
   Wdays[2] = "Wednes";
   Wdays[3] = "Thurs";
   Wdays[4] = "Fri";
   Wdays[5] = "Satur";
   Wdays[6] = "Sun";
}
stringdayType::setday() //Function to set the day
{
   if (day == Wdays[0])
   {
       i = 0;
   }
   elseif (day == Wdays[1])
   {
       i = 1;
   }
   elseif (day == Wdays[2])
   {
       i = 2;
   }
   elseif (day == Wdays[3])
   {
       i = 3;
   }
   elseif (day == Wdays[4])
   {
       i = 4;
   }
   elseif (day == Wdays[5])
   {
       i = 5;
   }
   elseif (day == Wdays[6])
       i = 6;
   else
   {
       day = "Invalid Input";
       i = 7;
   }
   return day;
}
stringdayType::preday() //Function to find the preivous day
{
   if (i == 0)
       prDay = Wdays[6];
   elseif (i == 7)
       prDay = "Invalid Input";
   else
       prDay = Wdays[i - 1];
   return prDay;
}
voiddayType::Nextday() //Function to find Next day
{
   if (i == 6)
       NxtDay = Wdays[0];
   elseif (i == 7)
       prDay = "Invalid Input";
   else
       NxtDay = Wdays[i + 1];
}
stringdayType::add(intn) // function to find after adding the number of days given by the user
{
   n = n + i;
   while (n>= 7)
   {
       n = n - 7;
   }
   if (i == 7)
       Wdays[n] = "Invalid Input ";
   return AddDays = Wdays[n];
}
voiddayType::print()
{
   cout << endl <<"\tDay="<< day <<"day"<< endl;
   cout <<"\tPrevious day :"<< prDay <<"day"<< endl;
   cout <<"\tNext day :"<< NxtDay <<"day"<< endl;
   cout <<"\tAfter Adding Days :"<< AddDays <<"day"<< endl;
}
void menu() //Function to display menu
{
   cout <<"******************MENU********************"<< endl;
   cout <<"\tEnter 'Sun' for 'Sunday'"<< endl;
   cout <<"\tEnter 'Mon' for 'Monday'"<< endl;
   cout <<"\tEnter 'Tues' for 'Tuesday'"<< endl;
   cout <<"\tEnter 'Wednes' for 'Wednesday'"<< endl;
   cout <<"\tEnter 'Thurs' for 'Thursday'"<< endl;
   cout <<"\tEnter 'Fri' for 'Friday'"<< endl;
   cout <<"\tEnter 'Satur' for 'Saturday'"<< endl;
