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 lukija = new Scanner(System.in);
        int n = lukija.nextInt();
        String stepSeq = lukija.next();
        String[] steps = new String[n];
        
        for (int step_i = 0; step_i < n; step_i++) {
            steps[step_i] = String.valueOf(stepSeq.charAt(step_i));
            
        }
        
        boolean valley = false;
        int numberOfValleys = 0;
        int level = 0;
        
        for (int i = 0; i < steps.length; i++) {
            if (steps[i].equals("U")) {
                level++;
                if (valley && level >= 0) {
                    valley = false;
                }
            } else {
                level--;
                if (!valley && level < 0) {
                    valley = true;
                    numberOfValleys++;
                }
            }                        
        }
        
        System.out.println(numberOfValleys);
    }
}