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);
        String steps="";
        int N=scan.nextInt();
        while(scan.hasNextLine()){
             steps=scan.nextLine();
            if(steps.length()==0){
                continue;
            }
        }
        
        int level=0;
        int valley=0;
        int n_valley=0; 
        for(int i=0;i<N;i++){
            if(steps.charAt(i)=='U'){
                level++;
                if(level==0 && valley==1){
                    n_valley++;
                }
            }
             if(steps.charAt(i)=='D'){
                 if(level==0){
                   valley=1;
                 }
                level--;
            }
        }
        System.out.println(""+n_valley);
    }
}