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 len = Convert.ToInt32(Console.ReadLine());
            string trip = Console.ReadLine();
            CountingValleys valley = new CountingValleys();
            Console.WriteLine(valley.numValleys(trip, len));
            Console.ReadKey();
    }
}
   class CountingValleys {
        public int numValleys(string hikingTrip, int num) {
            int noValleys = 0;
            int sea_level = 0;
            bool isValleyStart = false;
            for(int i=0; i<num; i++) {
                if(hikingTrip[i] == 'U') {
                    sea_level++;
                    if(sea_level == 0) {
                        if(isValleyStart) {
                            noValleys++;
                            isValleyStart = false;
                        }
                    }
                }
                else if(hikingTrip[i] == 'D') {
                    sea_level--;
                    isValleyStart = true;
                }
            }
            return noValleys;
        }
    }