odd_occurrences.rb

# you can write to stdout for debugging purposes, e.g.
# puts "this is a debug message"

# this only gets 66% not sure what's wrong.

def solution(a)
  # write your code in Ruby 2.2
  result = 0
  buckets = {}
  index = 0
  a.each do |num|
    buckets[num] = Array.new if buckets[num].nil?
    buckets[num].push index
    index = index + 1
  end
  
  buckets.each do |k, v|
    # puts "bucket = #{v}"
    if v.length == 1
      # puts "bucket = #{bucket}"
      result = k
    end
  end
  
  return result
end