# Enter your code here. Read input from STDIN. Print output to STDOUT
n = gets.strip.to_i
topography = gets.strip.split('')
valleys = 0
previous_height = 0
current_height = 0
topography.each do |step|
  if step == "U"
    current_height += 1
  else
    current_height -= 1
  end
  if previous_height == 0 && current_height == -1
    valleys += 1
  end
  previous_height = current_height
end
puts valleys