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 sc = new Scanner (System.in);
        
        int n  = sc.nextInt();
        String s = sc.next();
        
        int curL = 0;
        int valCount = 0;
        
        for(int i=0; i<n; i++){
            char tmp = s.charAt(i);
            if(tmp == 'U'){
               curL++; 
            }else{
                if(curL==0){
                    valCount++;
                }
                curL--;
            }
            
        }
       
        System.out.println(valCount);
       
        
    }
}