using System;
using System.Collections.Generic;
using System.IO;
class Solution {
    static void Main(String[] args) {
        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution */
        int n = Int32.Parse(Console.ReadLine());
        string steps = Console.ReadLine();
        
        int level = 0, valleyCount = 0;
        string lastDirection = "", currentDirection ="";
        bool startedAtSeaLevel = true;
        
        
        
        for (int i = 0; i < steps.Length; i++){
            currentDirection = steps[i].ToString();
            switch (currentDirection){
                case "U":
                level ++;
                break;
                
                case "D":
                level --;
                break;
            }
            
            if (lastDirection != ""){
                if (lastDirection != currentDirection){
                    if (startedAtSeaLevel && lastDirection == "D")
                        valleyCount++;
                    
                    startedAtSeaLevel = false;
                }
            }
            
            lastDirection = currentDirection;
            
            if (level == 0){
                startedAtSeaLevel = true;
                lastDirection = "";
            }
                
            
           // Console.WriteLine(i + " : " + currentDirection + " : " + level + " : " + valleyCount + " : " + startedAtSeaLevel);     
        }        
        Console.WriteLine(valleyCount);
    }
}