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) {
        
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        
        char[] steps = sc.next().toCharArray();
        
        int numValleys = 0;
        int hikerLevel = 0;
        int previousHikerLevel = 0;
        for(char step : steps){
            if(step=='D'){
                previousHikerLevel = hikerLevel;
                hikerLevel--;
            }
            else{
                hikerLevel++;
            }
            
            if(hikerLevel < 0 && previousHikerLevel==0){
                numValleys++;
            }
        }
        
        System.out.println(numValleys);
    }
}