Homework 3. Due: Feb 25, 23:59pm. Section 1 (20 pts, 2 pts each) Multiple Choice Questions

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1 Homework 3 Due: Feb 25, 23:59pm Section 1 (20 pts, 2 pts each) Multiple Choice Questions Q1: A function that modifies an array by using pointer arithmetic such as ++ptr to process every value of the array should have a parameter that is: a. A nonconstant pointer to nonconstant data. b. A nonconstant pointer to constant data. c. A constant pointer to nonconstant data. d. A constant pointer to constant data. ANS: a. A nonconstant pointer to nonconstant data. Q2: A function that prints a string by using pointer arithmetic such as ++ptr to output each character should have a parameter that is: a. A nonconstant pointer to nonconstant data. b. A nonconstant pointer to constant data. c. A constant pointer to nonconstant data. d. A constant pointer to constant data. ANS: b. A nonconstant pointer to constant data. Q3: Member access specifiers (public and private) can appear: a. In any order and multiple times. b. In any order (public first or private first) but not multiple times. c. In any order and multiple times, if they have brackets separating each type. d. Outside a class definition. ANS: a. In any order and multiple times. Q4: A default constructor: a. Is a constructor that must receive no arguments. b. Is the constructor generated by the compiler when no constructor is provided by the programmer. c. Does not perform any initialization. d. Both (a) and (b). ANS: d. Both (a) and (b). Q5: Which of the following is not true of a destructor? a. It performs termination housekeeping. b. It is called before the system reclaims the object s memory. c. If the programmer does not explicitly provide a destructor, the compiler creates an empty destructor. d. It releases the object s memory. ANS: d. It releases the object s memory. Q6: Given the class definition: class CreateDestroy

2 public: CreateDestroy() cout << "constructor called, "; } ~CreateDestroy() cout << "destructor called, "; } }; What will the following program output? int main() } CreateDestroy c1; CreateDestroy c2; return 0; a. constructor called, destructor called, constructor called, destructor called, b. constructor called, destructor called, c. constructor called, constructor called, d. constructor called, constructor called, destructor called, destructor called, ANS: d. constructor called, constructor called, destructor called, destructor called, Q7: The assignment operator (=) can be used to: a. Test for equality. b. Copy data from one object to another. c. Compare two objects. d. Copy a class. ANS: b. Copy data from one object to another. Q8: Increment::Increment( int c, int i ) : increment ( i ) count = c; } does not cause any compilation errors. This tells you that: a. count must be a non-const variable. b. count must be a const variable. c. increment must be a non-const variable. d. increment must be a const variable. ANS a. count must be a non-const variable. Q9: If the line: friend class A; appears in class B, and the line: friend class B; appears in class C, then: a. Class A is a friend of class C. b. Class A can access private variables of class B.

3 c. Class C can call class A s private member functions. d. Class B can access class A s private variables. ANS: b. Class A can access private variables of class B Q10: For a non-constant member function of class Test, the this pointer has type: a. const Test * b. Test * const c. Test const * d. const Test * const ANS: b. Test * const Section 2 Programming questions All the questions are in the required textbook: Question % // Exercise 9.8 Solution: Ex09_08.cpp #include <iostream> #include "Date.h" // include definitions of class Date using namespace std; int main() const unsigned int MAXDAYS = 16; Date d( 12, 24, 2013 ); // instantiate object d of class Date // output Date object d's value for ( unsigned int loop = 1; loop <= MAXDAYS; ++loop ) d.print(); // invokes function print

4 d.nextday(); // invokes function next day } // end for cout << endl; } // end main // Exercise 9.8 Solution: Date.h #ifndef DATE_H #define DATE_H class Date public: explicit Date( int = 1, int = 1, int = 2000 ); // default constructor void print(); // print function void setdate( int, int, int ); // set month, day, year void setmonth( int ); // set month void setday( int ); // set day void setyear( int ); // set year unsigned int getmonth() const; // get month unsigned int getday() const; // get day unsigned int getyear() const; // get year void nextday(); // next day private:

5 unsigned int month; unsigned int day; unsigned int year; bool leapyear() const; // leap year int monthdays() const; // days in month }; // end class Date #endif // Exercise 9.8 Solution: Date.cpp // Member-function definitions for class Date. #include <iostream> #include <stdexcept> #include <array> #include "Date.h" // include definition of class Date using namespace std; Date::Date( int m, int d, int y ) setdate( m, d, y ); // sets date } // end Date constructor void Date::setDate( int mo, int dy, int yr )

6 setmonth( mo ); // invokes function setmonth setday( dy ); // invokes function setday setyear( yr ); // invokes function setyear } // end function setdate void Date::setDay( int d ) if ( month == 2 && leapyear() && d <= 29 && d >= 1 ) day = d; else if ( d <= monthdays() && d >= 1 ) day = d; else throw invalid_argument( "day out of range for current month" ); } // end function setday void Date::setMonth( int m ) if ( m <= 12 && m >= 1 ) month = m; else throw invalid_argument( "month invalid" ); } // end function setmonth void Date::setYear( int y )

7 if ( y >= 2000 ) year = y; else throw invalid_argument( "year invalid" ); } // end function setyear unsigned int Date::getDay() const return day; } // end function getday unsigned int Date::getMonth() const return month; } // end function getmonth unsigned int Date::getYear() const return year; } // end function getyear void Date::print()

8 cout << month << '-' << day << '-' << year << '\n'; // outputs date } // end function print void Date::nextDay() try setday( getday() + 1 ); // increments day by 1 } catch ( invalid_argument & ) setday( 1 ); try setmonth( getmonth() + 1 ); } catch ( invalid_argument & ) setmonth( 1 ); setyear( getyear() + 1 ); } } } // end function nextday

9 bool Date::leapYear() const if ( year % 400 == 0 ( year % 4 == 0 && year % 100!= 0 ) ) return true; // is a leap year else return false; // is not a leap year } // end function leapyear int Date::monthDays() const const array< int, 12 > days = 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }; return month == 2 && leapyear()? 29 : days[ month - 1 ]; } // end function monthdays

10 Question % #include "TicTacToe.h" // include definition of class TicTacToe int main() TicTacToe g; // creates object g of class TicTacToe g.makemove(); // invokes function makemove } // end main // Exercise 9.15 Solution: TicTacToe.h #ifndef TICTACTOE_H #define TICTACTOE_H #include <array> class TicTacToe private: enum Status WIN, DRAW, CONTINUE }; // enumeration constants std::array< std::array< int, 3 >, 3 > board; public: TicTacToe(); // default constructor void makemove(); // make move void printboard() const; // print board

11 bool validmove( int, int ) const; // validate move bool xomove( int ); // x o move Status gamestatus() const; // game status }; // end class TicTacToe #endif // Exercise 9.15 Solution: TicTacToe.cpp // Member-function definitions for class TicTacToe. #include <iostream> #include <iomanip> #include "TicTacToe.h" // include definition of class TicTacToe using namespace std; TicTacToe::TicTacToe() for ( int j = 0; j < 3; ++j ) // initialize board for ( int k = 0; k < 3; ++k ) board[ j ][ k ] = ' '; } // end TicTacToe constructor bool TicTacToe::validMove( int r, int c ) const

12 return r >= 0 && r < 3 && c >= 0 && c < 3 && board[ r ][ c ] == ' '; } // end function validmove // must specify that type Status is part of the TicTacToe class. TicTacToe::Status TicTacToe::gameStatus() const int a; // check for a win on diagonals if ( board[ 0 ][ 0 ]!= ' ' && board[ 0 ][ 0 ] == board[ 1 ][ 1 ] && board[ 0 ][ 0 ] == board[ 2 ][ 2 ] ) return WIN; else if ( board[ 2 ][ 0 ]!= ' ' && board[ 2 ][ 0 ] == board[ 1 ][ 1 ] && board[ 2 ][ 0 ] == board[ 0 ][ 2 ] ) return WIN; // check for win in rows for ( a = 0; a < 3; ++a ) if ( board[ a ][ 0 ]!= ' ' && board[ a ][ 0 ] == board[ a ][ 1 ] && board[ a ][ 0 ] == board[ a ][ 2 ] ) return WIN; // check for win in columns

13 for ( a = 0; a < 3; ++a ) if ( board[ 0 ][ a ]!= ' ' && board[ 0 ][ a ] == board[ 1 ][ a ] && board[ 0 ][ a ] == board[ 2 ][ a ] ) return WIN; // check for a completed game for ( int r = 0; r < 3; ++r ) for ( int c = 0; c < 3; ++c ) if ( board[ r ][ c ] == ' ' ) return CONTINUE; // game is not finished return DRAW; // game is a draw } // end function gamestatus void TicTacToe::printBoard() const cout << " 0 1 2\n\n"; for ( int r = 0; r < 3; ++r ) cout << r; for ( int c = 0; c < 3; ++c )

14 cout << setw( 3 ) << static_cast< char > ( board[ r ][ c ] ); if ( c!= 2 ) cout << " "; } // end for if ( r!= 2 ) cout << "\n \n \n"; } // end for cout << "\n\n"; } // end function printboard void TicTacToe::makeMove() printboard(); while ( true ) if ( xomove( 'X' ) ) break; else if ( xomove( 'O' ) ) break; } // end while structure

15 } // end function makemove bool TicTacToe::xoMove( int symbol ) int x; int y; do cout << "Player " << static_cast< char >( symbol ) << " enter move: "; cin >> x >> y; cout << '\n'; } while (!validmove( x, y ) ); board[ x ][ y ] = symbol; printboard(); Status xostatus = gamestatus(); if ( xostatus == WIN ) cout << "Player " << static_cast< char >( symbol ) << " wins!\n"; return true; } // end if

16 else if ( xostatus == DRAW ) cout << "Game is a draw.\n"; return true; } // end else if else // CONTINUE return false; } // end function xomove

17 Question % // Exercise 9.23 Solution: ex09_23.cpp // Card shuffling and dealing program. #include <iostream> #include <iomanip> #include "DeckOfCards.h" // DeckOfCards class definition using namespace std; int main() DeckOfCards mydeckofcards; mydeckofcards.shuffle(); // place Cards in random order // print all 52 Cards in the order in which they are dealt for ( int i = 1; mydeckofcards.morecards(); ++i ) // deal and display a Card cout << left << setw( 19 ) << mydeckofcards.dealcard().tostring(); if ( i % 4 == 0 ) // output newline every 4 cards cout << endl; } // end for } // end main

18 // Exercise 9.23 Solution: Card.h // Class Card represents the face and suit of a card. #ifndef CARD_H #define CARD_H #include <string> class Card public: static const size_t FACES = 13; // total number of faces static const size_t SUITS = 4; // total number of suits Card( int cardface, int cardsuit ); // initialize face and suit std::string tostring() const; // returns a string representation of a Card // get the card's face int getface() const return face; } // end function getface // get the card's suit

19 int getsuit() const return suit; } // end function getsuit private: int face; int suit; static const std::string facenames[ FACES ]; static const std::string suitnames[ SUITS ]; }; // end class Card #endif // Exercise 9.23 Solution: Card.cpp // Member-function definitions and array initializers for the Card class. #include "Card.h" using namespace std; // contents of arrays to convert index into name const string Card::faceNames[ FACES ] = "Ace", "Deuce", "Three", "Four", "Five", "Six",

20 "Seven", "Eight", "Nine", "Ten", "Jack", "Queen", "King" }; const string Card::suitNames[ SUITS ] = "Hearts", "Diamonds", "Clubs", "Spades" }; // Card constructor initializes face and suit Card::Card( int cardface, int cardsuit ) face = ( cardface >= 0 && cardface < FACES )? cardface : 0; suit = ( cardsuit >= 0 && cardsuit < SUITS )? cardsuit : 0; } // end Card constructor // returns a string representation of a Card string Card::toString() const // strings can be concatenated with + return facenames[ face ] + " of " + suitnames[ suit ]; } // end function tostring // Exercise 9.23 Solution: DeckOfCards.h // Class DeckOfCards represents a deck of 52 playing cards. #ifndef DECK_OF_CARDS_H #define DECK_OF_CARDS_H

21 #include <vector> #include "Card.h" // DeckOfCards class definition class DeckOfCards public: DeckOfCards(); // constructor initializes deck void shuffle(); // shuffles cards in deck Card dealcard(); // deals cards in deck bool morecards() const; // are there any more cards left private: std::vector< Card > deck; // represents deck of cards unsigned currentcard; // index of next card to be dealt }; // end class DeckOfCards #endif // Exercise 9.23 Solution: DeckOfCards.cpp // Member-function definitions for class DeckOfCards that simulates // the shuffling and dealing of a deck of playing cards. #include <random> // contains C++11 random number generation features #include <ctime>

22 #include "DeckOfCards.h" // DeckOfCards class definition using namespace std; default_random_engine engine( static_cast<unsigned int>( time(0) ) ); // DeckOfCards default constructor initializes deck DeckOfCards::DeckOfCards() currentcard = 0; // set currentcard so first Card dealt is deck[ 0 ] // populate deck with Card objects for ( size_t i = 0; i < Card::FACES * Card::SUITS; ++i ) Card card( i % Card::FACES, i / Card::SUITS ); deck.push_back( card ); // adds copy of card to the end of the deck } // end for } // end DeckOfCards default constructor // shuffle cards in deck void DeckOfCards::shuffle() uniform_int_distribution<size_t> randomint( 0, deck.size() - 1 ); // after shuffling, dealing should start at deck[ 0 ] again

23 currentcard = 0; // reinitialize currentcard // for each Card, pick another random Card and swap them for ( size_t first = 0; first < deck.size(); ++first ) // select a random number between 0 and 51 unsigned second = randomint( engine ); // swap current Card with randomly selected Card Card temp = deck[ first ]; deck[ first ] = deck[ second ]; deck[ second ] = temp; } // end for } // end function shuffle // deal cards in deck Card DeckOfCards::dealCard() return deck[ currentcard++ ]; // return current Card in vector } // end function dealcard // Check if there are more cards in the deck bool DeckOfCards::moreCards() const

24 return currentcard < deck.size(); } // end function morecards

25 Question % // Exercise 9.24 Solution: ex09_24.cpp // Card shuffling and dealing program. #include <iostream> #include <iomanip> #include "DeckOfCards.h" // DeckOfCards class definition #include "Hand.h" // Hand class definition using namespace std; int main() DeckOfCards mydeckofcards; mydeckofcards.shuffle(); // place Cards in random order Hand hand( mydeckofcards ); // deal a hand from the deck hand.print(); // display hand // check for each type of hand by decreasing ranking if ( hand.fourofakind() ) cout << "Hand contains four of a kind" << endl; else if ( hand.flush() && hand.straight() ) cout << "Hand contains a straight flush" << endl; else if ( hand.flush() ) cout << "Hand contains a flush" << endl;

26 else if ( hand.straight() ) cout << "Hand contains a straight" << endl; else if ( hand.threeofakind() ) cout << "Hand contains three of a kind" << endl; else if ( hand.twopair() ) cout << "Hand contains two pairs" << endl; else if ( hand.pair() ) cout << "Hand contains a pair" << endl; } // end main // Exercise 9.24 Solution: Card.h // Class Card represents the face and suit of a card. #ifndef CARD_H #define CARD_H #include <string> class Card public: static const size_t FACES = 13; // total number of faces

27 static const size_t SUITS = 4; // total number of suits Card( int cardface, int cardsuit ); // initialize face and suit std::string tostring() const; // returns a string representation of a Card // get the card's face int getface() const return face; } // end function getface // get the card's suit int getsuit() const return suit; } // end function getsuit private: int face; int suit; static const std::string facenames[ FACES ]; static const std::string suitnames[ SUITS ]; }; // end class Card

28 #endif // Exercise 9.24 Solution: Card.cpp // Member-function definitions and array initializers for the Card class. #include "Card.h" using namespace std; // contents of arrays to convert index into name const string Card::faceNames[ FACES ] = "Ace", "Deuce", "Three", "Four", "Five", "Six", "Seven", "Eight", "Nine", "Ten", "Jack", "Queen", "King" }; const string Card::suitNames[ SUITS ] = "Hearts", "Diamonds", "Clubs", "Spades" }; // Card constructor initializes face and suit Card::Card( int cardface, int cardsuit ) face = ( cardface >= 0 && cardface < FACES )? cardface : 0; suit = ( cardsuit >= 0 && cardsuit < SUITS )? cardsuit : 0; } // end Card constructor // returns a string representation of a Card string Card::toString() const // strings can be concatenated with +

29 return facenames[ face ] + " of " + suitnames[ suit ]; } // end function tostring // Exercise 9.24 Solution: DeckOfCards.h // Class DeckOfCards represents a deck of 52 playing cards. #ifndef DECK_OF_CARDS_H #define DECK_OF_CARDS_H #include <vector> #include "Card.h" // DeckOfCards class definition class DeckOfCards public: DeckOfCards(); // constructor initializes deck void shuffle(); // shuffles cards in deck Card dealcard(); // deals cards in deck bool morecards() const; // are there any more cards left private: std::vector< Card > deck; // represents deck of cards unsigned currentcard; // index of next card to be dealt

30 }; // end class DeckOfCards #endif // Exercise 9.24 Solution: DeckOfCards.cpp // Member-function definitions for class DeckOfCards that simulates // the shuffling and dealing of a deck of playing cards. #include <random> // contains C++11 random number generation features #include <ctime> #include "DeckOfCards.h" // DeckOfCards class definition using namespace std; default_random_engine engine( static_cast<unsigned int>( time(0) ) ); // DeckOfCards default constructor initializes deck DeckOfCards::DeckOfCards() currentcard = 0; // set currentcard so first Card dealt is deck[ 0 ] // populate deck with Card objects for ( size_t i = 0; i < Card::FACES * Card::SUITS; ++i )

31 Card card( i % Card::FACES, i / Card::SUITS ); deck.push_back( card ); // adds copy of card to the end of the deck } // end for } // end DeckOfCards default constructor // shuffle cards in deck void DeckOfCards::shuffle() uniform_int_distribution<size_t> randomint( 0, deck.size() - 1 ); // after shuffling, dealing should start at deck[ 0 ] again currentcard = 0; // reinitialize currentcard // for each Card, pick another random Card and swap them for ( size_t first = 0; first < deck.size(); ++first ) // select a random number between 0 and 51 unsigned second = randomint( engine ); // swap current Card with randomly selected Card Card temp = deck[ first ]; deck[ first ] = deck[ second ]; deck[ second ] = temp; } // end for

32 } // end function shuffle // deal cards in deck Card DeckOfCards::dealCard() return deck[ currentcard++ ]; // return current Card in vector } // end function dealcard // Check if there are more cards in the deck bool DeckOfCards::moreCards() const return currentcard < deck.size(); } // end function morecards // Exercise 9.24 Solution: Hand.h // Stores and calculates attributes of a hand of cards. #ifndef HAND_H #define HAND_H #include <string> #include <vector> #include "Card.h"

33 #include "DeckOfCards.h" class Hand public: // constructor takes 5 cards from Deck Hand( DeckOfCards &deck ); void print() const; // display hand // determine if we have the given scoring hand bool pair() const; bool twopair() const; bool threeofakind() const; bool fourofakind() const; bool flush() const; bool straight() const; private: std::vector< Card > hand; // our hand std::vector< int > facecount; // number of each face }; // end class Hand #endif

34 // Exercise 9.24 Solution: Hand.cpp // Stores and calculates attributes of a hand of cards. #include <iostream> #include "Hand.h" using namespace std; // constructor takes 5 cards from Deck; it assumes 5 cards are available Hand::Hand( DeckOfCards &deck ) : facecount( Card::FACES ) // get hand from deck for ( unsigned i = 0; i < 5; ++i ) hand.push_back( deck.dealcard() ); // count number of times each face appears (for later use) for ( unsigned i = 0; i < hand.size(); ++i ) ++facecount[ hand[ i ].getface() ]; } // end constructor // display contents of hand to standard output stream void Hand::print() const cout << "Hand is:\n";

35 for ( unsigned i = 0; i < hand.size(); ++i ) cout << hand[ i ].tostring() << '\n'; cout << endl; } // end function print // determine if hand contains a pair bool Hand::pair() const for ( unsigned i = 0; i < facecount.size(); ++i ) if ( facecount[ i ] == 2 ) return true; return false; } // end function pair // determine if hand contains two pairs bool Hand::twoPair() const bool foundone = false; // true if the first pair has been found for ( unsigned i = 0; i < facecount.size(); ++i ) if ( facecount[ i ] == 2 && foundone ) return true; // found both pairs

36 else if ( facecount[ i ] == 2 ) foundone = true; // found the first pair } // end for return false; // didn't find both pairs } // end function twopair // determine if hand contains three of a kind bool Hand::threeOfAKind() const for ( unsigned i = 0; i < facecount.size(); ++i ) if ( facecount[ i ] == 3 ) return true; return false; } // end function threeofakind // determine if hand contains four of a kind bool Hand::fourOfAKind() const for ( unsigned i = 0; i < facecount.size(); ++i ) if ( facecount[ i ] == 4 ) return true;

37 return false; } // end function fourofakind // determine if hand contains a flush bool Hand::flush() const int suit = hand[ 0 ].getsuit(); // search for any card that has a suit different from the first for ( unsigned i = 1; i < hand.size(); ++i ) if ( hand[ i ].getsuit()!= suit ) return false; return true; } // end function flush // determine if hand contains a straight bool Hand::straight() const vector< int > tmp = facecount; // make a temporary copy of face count tmp.push_back( tmp[ 0 ] ); // ace can also be used as the high card // special case: ace straight if ( tmp[ 0 ] == 1 && tmp[ 1 ] == 1 && tmp[ 2 ] == 1 &&

38 tmp[ 3 ] == 1 && tmp[ 4 ] == 1 ) return true; unsigned i = 1; // counter to hold current position // search for first non-zero face count while ( i < tmp.size() && tmp[ i ] == 0 ) ++i; unsigned start = i; // save position // count consecutive frequencies of 1 while ( i < tmp.size() && tmp[ i ] == 1 ) ++i; return i == start + 5; // should have counted 5 faces with frequency 1 } // end function straight

//main.cpp. using namespace std;

//main.cpp. using namespace std; Eric Villanueva CSE 330 Homework 1 (40/40) I d give myself a full 40 out of 40 points. I put a lot of effort into getting my code to work, I also used my own code for most of it. Question 1) #include