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

public class Solution {

    public static void main(String[] args) {
        Scanner s=new Scanner(System.in);
        int steps=s.nextInt();
        char[] seq= s.nextLine().toCharArray();
         seq= s.nextLine().toCharArray();
        int level=0;
        int valleys=0;
        boolean valleyStart=false;
         //System.out.println("jaja");
        for(int i=0;i<steps;i++)
        {
            //System.out.println(level+" "+seq[i]);
            if(level==0 && seq[i]=='D'){
                valleyStart=true;
            }
            if(level==-1 && seq[i]=='U' && valleyStart){
                valleyStart=false;
                valleys++;                
            }
            if(seq[i]=='D'){               
            level--;
            }
            else{
                level++;
            }           
            
        }
        System.out.println(valleys);
    }
}