See Buildings to the Left

see_buildings_left.rb

# Given a list of integers representing the heights of buildings,
# return the maximum number of buildings that can be seen when
# looking from the left. A building can see another building if
# it is taller than all the buildings to its left. The height of
# the tallest building is included in the count.
def see_buildings_left(buildings)
  return 0 if buildings.empty?

  buildings.each_cons(2).inject(1) do |count, (a, b)|
    count += 1 if a < b
    count
  end
end

see_buildings_left([])
=> 0

see_buildings_left([1,2,3,4,5])
# => 5

see_buildings_left([5,4,3,2,1])
# => 1

see_buildings_left([3,7,8,3,6,1])
# => 3

see_buildings_left([1,1,2,2,2,2,6,3,1,10])
=> 4