object Solution {

    def main(args: Array[String]) {           
        def stepToLevel(step: Char, lastLevel: Int): Int = step match {
            case 'U' => lastLevel + 1
            case 'D' => lastLevel - 1
        }
            
        def stepsToLevel(steps: List[Char], acc: List[Int]): List[Int] = steps match {
            case List() => acc
            case x :: xs => stepsToLevel(xs, stepToLevel(x, acc.head) :: acc)    
        }
        
        def countValeys(levels: List[Int], acc: Int): Int = levels match {
            case x :: y :: xs => countValeys(levels.tail, if (x == 0 && y < 0) acc + 1 else acc)
            case _ => acc
        }
            
        
        val sc = new java.util.Scanner(System.in)
        val steps = sc.nextInt()
        sc.nextLine()
        val line = sc.nextLine()
        System.out.println(countValeys(stepsToLevel(line.toList, List(0)), 0))    
    }
}