using System;
using System.Collections.Generic;
using System.IO;
class Solution {
    static void Main(String[] args) {
        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution */
        int n = int.Parse(Console.ReadLine());
        string steps = Console.ReadLine();
        int sealevel = 0;
        Boolean valleyflag = false;
        int countValleys = 0;
        for(int x=0; x<=(n-1); ++x){
            if(steps[x]=='D'){
               sealevel = sealevel - 1;
            }else{
               sealevel = sealevel + 1; 
            }
            if (sealevel <= -1){
                //He is entering a valley set flag.
                valleyflag = true;
            }
            if (sealevel == 0 && valleyflag==true){
                //exiting valey set flag
                valleyflag = false;
                countValleys = countValleys + 1;
            }
        }
        Console.WriteLine(countValleys.ToString());
    }
}