# Iterate through the array from both sides to find the index of search_item. def double_linear_search(array, search_item) start_ind = 0 end_ind = array.length - 1 while start_ind <= end_ind return start_ind if array[start_ind] == search_item return end_ind if array[end_ind] == search_item start_ind += 1 end_ind -= 1 end # returns -1 if search_item is not found in array -1 end puts(double_linear_search([1, 5, 5, 10], 1)) # => 0 puts(double_linear_search([1, 5, 5, 10], 5)) # => 1 puts(double_linear_search([1, 5, 5, 10], 100)) # => -1 puts(double_linear_search([1, 5, 5, 10], 10)) # => 3