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

public class Solution {

    public static void main(String[] args) throws IOException {
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));
        bufferedReader.readLine();
        String path = bufferedReader.readLine();
        String[] pathSplit = path.split("");

        int valleys = 0, hills = 0;
        int currentLevel = 0;
        for (String pathItem : pathSplit) {
            if (pathItem.equals("U")) {
                currentLevel++;
            } else {
                if (currentLevel == 0) {
                    valleys++;
                }
                currentLevel--;
            }
        }
        System.out.println(valleys);
    }
}