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);
        int steps = scan.nextInt();
        String s = scan.next();
        
        boolean inValley = false;
        int level = 0;
        int valleys = 0;
        
        for (int i = 0; i < s.length(); i++){
            char step = s.charAt(i);
            if (step == 'U'){
                level++;
                if (inValley && level == 0){
                    inValley = false;
                }
            }
            else {
                level--;
                if (!inValley && level < 0){
                    inValley = true;
                    valleys++;
                }
            }
        }
        
        System.out.println(valleys);
    }
}