//https://www.hackerrank.com/contests/rookierank/challenges/birthday-cake-candles

import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

    public static void main(String[] args) {
        
        Scanner in = new Scanner(System.in);
        
        int n = in.nextInt();
        
        in.nextLine();
        String s = in.nextLine();
        
        int valleys = 0, level = 0, past1 = 0;
        //boolean in_valley = false;
        
        for(int i = 0; i < n; i++){
            //if (level == 0 && s.charAt(i) == 'D') {
            //    in_valley = true;
            //}
            if (level == -1 && s.charAt(i) == 'U') {
                //in_valley = false;
                valleys++;
            }
            
            past1 = level;
            if (s.charAt(i) == 'D') {level--;}
            else {level++;}
        }
        
        System.out.println(valleys);
    }
}