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) {
        /* 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 stepCount = scan.nextInt();
        scan.nextLine();
        String steps = scan.next();
        char[] chars = steps.toCharArray();
        int currentLevel = 0;
        int previousLevel = 0;
        int walleyCount = 0;
        for(char c : chars) {
            previousLevel = currentLevel;
            if(c == 'U') {
                currentLevel++;
            } else {
                currentLevel--;
            }
            if(currentLevel >=0 && previousLevel < 0) {
                walleyCount++;
            }
        }
        System.out.print(walleyCount);
    }
}