Comp 1572, Winter 2002
Pencil-and-Paper Assignment 6
Assigned Friday, February 22, 2002
Due Friday, March 1, 2002 (At the beginning of class)

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solutions
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1.  Both constructor definitions cannot exist in the same class, because the
    first definition has default values, and thus *is already* a default
    constructor.  There is an ambiguity - if no parameters are passed to
    the constructor, the compiler wouldn't know which function to call.  So
    this is not allowed.

2.  There are many solutions.  Here is one:
    char * search_for_char(char *arr, char key)
    {
        char *p;
        for (p=arr; *p != 0; p++) {
            if (*p == key) return p;
        }
        return 0;  // not found!
    }

3.  Given the following class 
    class Employee {
    public:
        Employee(); //default constructor
        Employee(const char *, const char *); // constructor
        ~Employee(); //destructor
        const char *getFirstName() const;  // return first name
        const char *getLastName() const;   // return last name
        void setLastName(char *);          // set employee last name
        void setFirstName(char *);         // set employee first name
    private:
        char *firstName;
        char *lastName;
    }; 
    Write a program that will ask the user how many employees there are,
    dynamically allocate an array of Employees of the appropriate size,
    input from the user the data for each employee and update the
    Employees in the array, traverse the array and display the data,
    delete the dynamically allocated memory, and exit.
    int main()
    {
        int numemp;
        Employee *elist;
        cout << "How many employees? ";
        cin >> numemp;
        char firstname[80], lastname[80];
        
        elist = new Employee[numemp];
        for (i=0; i < numemp; i++) {
	   cout << "Input first and last name of employee number " << i << ": ";
           cin >> firstname  >> lastname;
           elist[i].setFirstName(firstname);
           elist[i].setLastName(lastname);
        }
        for (i=0; i <numemp; i++) {
           cout << elist[i].getFirstName() << " ";
           cout << elist[i].getLastName() << endl;
        }

        delete [] elist;
    }
4.  
   class proxy_for_time { 
        proxy_for_time();               // default constructor
        proxy_for_time(int, int, int);  // constructor takes hour, min, sec
        void setTime(int, int, int);  // set hour, minute, second
        void printMilitary() const;   // print military time format
        void printStandard() const;   // print standard time format
        ~proxy_for_time();
    private:
        Internal_version_of_Time *ptr;
   };

   proxy_for_time::proxy_for_time()
   : ptr(new Internal_version_of_Time()) {}

   proxy_for_time::proxy_for_time(int i1, int i2, int i3)
   : ptr(new Internal_version_of_Time(i1,i2,i3)) {}


   proxy_for_time::~proxy_for_time()
   { delete ptr; }
   proxy_for_time::setTime(int i1, int i2, int i3)

   { ptr->setTime(i1,i2,i3); }

   proxy_for_time::printMilitary() const
   { ptr->printMilitary(); }

   proxy_for_time::printStandard() const
   { ptr->printStandard(); }