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) {
 if(st.charAt(i)=='D'){
          count--;
      }else if(st.charAt(i)=='U'){
          count++;
      }


    if(count<0){


        if(st.substring(i,i+3).equals("DDU")){
             //System.out.println(""+st.substring(i,i+2));
            vally++;
        }
    }



}    

    }
System.out.println(""+vally);
}