using System;


namespace Candles
{
    public class Program
    {
        static void Main(string[] args)
        {
            int n = Int32.Parse(Console.ReadLine());
            string input = Console.ReadLine();
            int sealevel = 0;
            int valley = 0;
            int mountain = 0;
            int direction = input[0] == 'U' ? 0 : 1;
            foreach(var step in input.ToCharArray())
            {
                if (step == 'U')
                {
                    sealevel++;
                }
                else if (step == 'D')
                {
                    sealevel--;
                }
                if(sealevel == 1 && direction == 0)
                {
                    mountain++;
                }
                else if(sealevel == 0 && direction == 0)
                {
                    direction = 1;
                }
                else if(sealevel == 0 && direction == 1)
                {
                    valley++;
                }
                else if (sealevel == 1 && direction == 1)
                {
                    direction = 0;
                }
            }
            Console.WriteLine(valley);
        }
    }
}