Week 4: Exercises

1. Hands of Cards

Consider this class:

enum Suit { Clubs, Diamonds, Hearts, Spades };

class Card {
    public int rank;    // 1 = Ace, 2 .. 10, 11 = Jack, 12 = Queen, 13 = King 
    public Suit suit;

    public Card(int rank, Suit suit) {
        this.rank = rank;
        this.suit = suit;
    }

}

a) Add a method string describe() that returns a string description such as "7 of Diamonds" or "Jack of Hearts".

b) Write a class Deck with these members:

• Deck() - return a new deck of 52 cards

• Card[] deal(int n) – return an array of n cards randomly chosen from the remaining cards in the Deck, and remove them from the deck. If fewer than n cards remain, return null.

• int count() - return the number of cards currently remaining in the deck

2. Dynamic Array

Write a class DynArray that represents a variable-sized array of integers, with indices starting at 0. It should have the following members:

• DynArray() - create a new empty DynArray

• int length() - return the current array length

• void append(int i) - append an integer to the array

• int get(int index) - read the integer at the given index

• void set(int index, int val) - set the integer at the given index, which must be within the current array bounds

What will be the average-case big-O running time of append()?

3. Binary Tree

Write a class BinaryTree that holds a binary tree of integers. Your class should have these members:

• BinaryTree() - create a BinaryTree that is initially empty

• void insert(int i) - insert a value into the tree if it is not already present

• bool contains(int i) - return true if the tree contains the value i, otherwise false

• int[] toArray() - return an array holding all the values in the binary tree, in ascending order