import java.io.*;
import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.stream.Collectors;
import java.util.stream.IntStream;

public class Solution {

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String s = br.readLine();

        int count = 0;
        int h = 0;

        for (char c : br.readLine().toCharArray()) {
            int prevH = h;
            h += c == 'U' ? 1 : -1;

            if (prevH == 0 && h < 0) {
                count++;
            }
        }
        System.out.println(count);
    }


}