# Enter your code here. Read input from STDIN. Print output to STDOUT
n = gets.strip.to_i
seq = gets.strip.split('')

def counting_valleys(seq)
  current_level = 0
  num_of_valleys = 0
  in_valley = false

  seq.each do |s|
    current_level += s == 'U' ? 1 : -1

    if current_level < 0 && !in_valley
      in_valley = true
    end

    if current_level == 0 && in_valley
      in_valley = false
      num_of_valleys += 1
    end
  end

  num_of_valleys
end


puts counting_valleys(seq)