import scala.math.random

object Solution {

	// turns a list of the characters "U" and "D" into a list of heights, and then
	// tests for crossings from height 0 to height -1
  def main(args: Array[String]) {
  	var level = -1;
		val numSteps = readInt
		// initial "U" from height -1 blocks the edge case of starting with a 
		// downward step.
		val numValleys = ("U" ++ readLine()) 
			.map(v=>if (v == 'U') {level += 1; level} else {level -= 1; level})
			.sliding(2)
			.filter(v=>(v(0) == 0 && v(1) < 0))
			.map(_=>1)
			.sum
		println(numValleys)
  }
}