algo for pointing out copies (modified insertion sort)

sort_and_find_copies.rb

def sort_and_find_copies(array)  
  array.each_with_index do |element, idx|  
    previous_idx = idx - 1  
    while previous_idx >= 0
      puts "#{array[previous_idx]} is a copy!" if  array[previous_idx] == element 
      break if array[previous_idx] <= element  
      array[previous_idx + 1] = array[previous_idx]  
      previous_idx -= 1  
    end  
    array[previous_idx + 1] = element  
  end  
end