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) {
        
        Scanner scan = new Scanner(System.in);
        
        // number of steps Gary took (from user input)
        int steps = scan.nextInt();
        
        // get "topography" string from input
        String topography = new String(scan.next());
        
        // debug
        /*
        System.out.println("Steps: " + steps);
        System.out.println("Topography: " + topography);
        */
        

        int elevation = 0; 
        int valleys = 0;
        
        // loop through string
        for (int i = 0; i < topography.length(); i++) {
            
            // get current char (up or down)
            if (topography.charAt(i) == 'U') {
                elevation += 1;
            }
            else if (topography.charAt(i) == 'D') {
                elevation -=1;
            }
            
            // check if below sealevel and going down (entering a valley)
            if (elevation == -1 && (topography.charAt(i) == 'D')) {
                valleys += 1;
            }
            // assume all valleys will be exited (because Gary's hike ends at sealevel)
        }
        // System.out.print("Number of valleys: ");
        System.out.println(valleys);
    }
}