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

public class Solution {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        in.nextLine();
        String steps = in.nextLine();
        int alt = 0;
        boolean beginOfValley = false;
        boolean endOfValley = false;
        int valleyCount = 0;
        
        for(int i=0; i<steps.length(); i++) {
            if(steps.charAt(i) == 'U') {
                alt++;
            }
            else {
                alt--;
            }
            if(alt < 0 && beginOfValley == false) {
                beginOfValley = true;
                valleyCount++;
            }
            if(alt >= 0 && beginOfValley == true) {
                beginOfValley = false;
            }
        }
        System.out.println(valleyCount);
    }
}