interview_questions.rb

# Here are a handful of good practice problems, some of which may show up in interviews.

# 1. Write an anagram function. 
# After that, try writing an anagram function without using #sort and iterating over each word only once
anagram("orchestra", "carthorse") # returns true
anagram("orchestra", "apple")     # returns false

# 2. Write a function to test for balanced parentheses. 
# This was a Twitter interview question, by the way.
balanced("()") # returns true
balanced(")()") # returns false

# 3. Implement binary search. 
# The function should accept a sorted array of integers and a desired integer.
# Return the index of the integer if it appears in the array. Otherwise, return -1
search([1, 2, ... 100], 35) # should return the index of 35

# 4. Write a function that when given an array of sorted integers and a number K,  
# returns the number of occurences for K in the array.
count_occurrences([1, 2, 3, 3, 3, 3, 4, 4], 3)       # returns 4
count_occurrences([1, 1, 1, 3, 3, 3, 3, 3, 3, 3], 1) # returns 3

# 5. Write a singly linked list

# 6. Write a function to delete a node from a singly linked list

# 7. Write a function to test if a word is a palindrome.
# Now write the same function but do not use #reverse

# 8. Write a function to test if a number is prime