# Enter your code here. Read input from STDIN. Print output to STDOUT

n = gets.to_i

inp = gets

f = false
v = 0
x = 0
inp.each_char { |c|
  if c == "U"
    x += 1
  else
    x -= 1
  end
  
  
  if x < 0
    f = true
  end
  
  if x == 0 and f
    f = false
    v += 1
  end
  
}

puts v