sort.rb

# Sort the array from lowest to highest
def sort(arr)
  a_length = arr.length
  return arr if a_length == 1
  return [] if a_length == 0
  keep_going = true
  while keep_going do
    flagged = false
    arr.each_with_index do |num,index|
      unless (index + 1 == arr.length ) # Can't compare last number with next one since it doesn't exist.
        flag = (num <=> arr[index+1]) 
        if flag == 1 # If the first number is smaller or equal than the second
          new_value = arr[index]
          arr[index] = arr[index + 1]   
          arr[index + 1] = new_value
        end
      end
    keep_going = false if flagged == false
    end
  end
  results = arr
end

# Find the maximum 
def maximum(arr)
  sort(arr).last
end

def minimum(arr)
  sort(arr).first
end
 
# expect it to return 42 below
result = maximum([2, 42, 22, 02])
puts "max of 2, 42, 22, 02 is: #{result}"

# expect it to return 2 below
result = minimum([2, 42, 22, 02])
puts "min of 2, 42, 22, 02 is: #{result}"

 
# expect it to return nil when empty array is passed in
result = maximum([])
puts "max on empty set is: #{result.inspect}"
result = minimum([])
puts "min on empty set is: #{result.inspect}"
 
result = maximum([-23, 0, -3])
puts "max of -23, 0, -3 is: #{result}"
 
result = maximum([6])
puts "max of just 6 is: #{result}"