import java.io.*;
import java.util.*;

public class Solution {

    public static void main(String[] args) {
        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
        
        Scanner scan = new Scanner(System.in);
        
        scan.nextLine();
        String input = scan.nextLine();
        
        int count = 0;
        int valleyCount = 0;
        int index = 0;
        
        for(char c : input.toCharArray()){

            
            
            if(c == 'U')
            {
                count++;    
            }
            else{
                count--;
            }
            
            if(index!=0 && count == 0 && c =='U'){
                valleyCount++;
            }
            
            index++;
        }
        System.out.println(valleyCount);
        
        
    }
}