Suppose you have the following array

stuff = [:dog,:cat,:orange,:banana]

1. How can you slice this array to create a new array [:cat,:orange]
2. Add the element :apple on to the end of the array.
3. Now take :apple back off again
4. Add the element :fish to the start of the array.
5. Now remove the element :fish.

The following code will fail with NoMethodError : private method 'dream' called for Dog

Assuming that you cannot modify the source code for the Dog class and that the method
must remain private - how can you nonetheless call this method from outside of Dog class?

class Dog
    def speak
        puts "woof"
    end

    private

    def dream
        puts "chasing a rabbit"
    end
end

dog = Dog.new
dog.speak
dog.dream

Start with an array of integers, 1 through 5. First, square all the elements in the array. Then, sum all the elements of the squared array.

Print out the prime numbers between 1 and 100. As a first pass, don't worry about writing an efficient algorithm. Just write clear code that is easy to follow. Once you've done that, consider different possible optimizations.

How do you share methods between different parts of your code in Ruby? Can you name three strategies for doing this? Discuss the pros and cons of each.

Suppose I have the following Array of tuples

[ ['a',1], ['b',2], ['c','3' ]

How can I convert this to a Hash?

{ 'a' => 1, 'b' => 2, 'c' => 3}

Once I've written the algorithm, how would I make it generally available throughout my Ruby application?

What will original and copy evaluate to in each of the following examples? Explain why there is a difference.

original = "hello"
copy = original
copy << " there"
puts copy
puts original

original = "hello"
copy = original
copy += " there"
puts copy
puts original

In each example below indicate whether or not we should be asserting true or false. (E.g. what should the ? be?).

Explain the difference between ==, eql and equal?

str1 = "chitter"
str2 = "chitter"

assert_equal ?, str1 == str2
assert_equal ?, str1.eql?(str2)
assert_equal ?, str1.equal?(str2)
assert_equal ?, str1.object_id == str2.object_id

sym1 = :chatter
sym2 = :chatter

assert_equal ?, sym1 == sym2
assert_equal ?, sym1.eql?(sym2)
assert_equal ?, sym1.equal?(sym2)
assert_equal ?, sym1.object_id == sym2.object_id

Write a string to find a substring in a given string. Do this in O(n) or better

Write an iterative function to reverse a string. Do the same thing as a recursive function.

Write a program to print out a multiplication table, from 1x1 to 12x12. This should look like:

   1   2   3   4   5   6   7   8   9  10  11  12
   2   4   6   8  10  12  14  16  18  20  22  24
   3   6   9  12  15  18  21  24  27  30  33  36
   4   8  12  16  20  24  28  32  36  40  44  48
   5  10  15  20  25  30  35  40  45  50  55  60
   6  12  18  24  30  36  42  48  54  60  66  72
   7  14  21  28  35  42  49  56  63  70  77  84
   8  16  24  32  40  48  56  64  72  80  88  96
   9  18  27  36  45  54  63  72  81  90  99 108
  10  20  30  40  50  60  70  80  90 100 110 120
  11  22  33  44  55  66  77  88  99 110 121 132
  12  24  36  48  60  72  84  96 108 120 132 144

Describe the difference between a class instance variable and a class variable in Ruby. Which bears more resemblance to a static field in Java?

What is a hashtable? Give an example of a type of problem that a hashtable is useful for.

For the data structures: Array and Linked List explain:

• Where you might use them
• Operations that are commonly supported (add, insert etc)

What's the value of hexadecimal FF in decimal?

Write a program to find the largest integer in an array of integers.

Write a function that sums up integers from a text file that looks like the following:

1
3
27
2
2123

Write function to print the odd numbers from 1 to 99

Write a program to open a file for reading and print out its entire contents

Write a function to take the following list and return one list of odd numbers and one list of even numbers:

ints = [1,21,53,84,50,66,7,38,9]

A user types the following URL into their browser: http://www.foo.com/bar.php

Explain in detail how this would cause a page to appear in their browser, with images, interactive elements (Ajax), styled paragraphs of text etc.

Explain what a deadlock is in multithreaded programming

Write a function that takes an integer and returns the smallest number that is greater than the given number which is a palendrome.

For example, if the input was 111 the next palindromic number would be 121.

Write a function, tokenize_string(input_string, delimiter_list) that returns a list of strings that are separated by the delimiters.

For example: tokenize_string("How now, Mrs. Brown Cow") returns ['How', 'now', 'Mrs', 'Brown', 'Cow']

Explain the terms "coupling" and "Cohesion". Is low coupling and high cohesion desirable? Why?

Model the animal kingdom as a set of classes. Discuss the species, their behavior and properties.

Explain the principles of test drive development.

Describe the singleton design pattern and how you might use it in practice.

Implement it.

Describe the MVC design pattern and how you might use it in practice.

Implement it.

Write a function to return the Nth number of Fibonacci sequence.

Design the schema or the classes to implement a library for building card games with. This library should make it easy to build games like Rummy, Poker, Hearts, Whist etc.

Outline the implementation for two of the most important methods of the Deck class.