using System.Collections.Generic;
using System;

public class Solution
{
    enum EnvironmentType
    { None=0, Montain, Valley}

    public static void Main(string[] args)
    {
        IInput input;

        if (args.Length > 0)
        {
            input = new StringInput(System.IO.File.ReadAllLines(args[0]));
        }
        else
        {
            input = new ConsoleInput();
        }

        var v = input.ReadLine();
        int stepsCount = int.Parse(v);
        var stepsStr = input.ReadLine();
        int level = 0;
        EnvironmentType type = EnvironmentType.None;
        int mountainCount = 0;
        int valleyCount = 0;

        for (int i = 0; i < stepsCount; i++)
        {
            if (stepsStr[i] == 'U')
            {
                level++;
            }
            else
            {
                level--;
            }

            if (level > 0)
            {
                type = EnvironmentType.Montain;
            }
            else if (level < 0)
            {
                type = EnvironmentType.Valley;
            }
            else
            {
                if (type == EnvironmentType.Montain)
                {
                    mountainCount++;
                }
                else if (type == EnvironmentType.Valley)
                {
                    valleyCount++;
                }

                type = EnvironmentType.None;
            }
        }

        Console.WriteLine(valleyCount);
    }

    public interface IInput
    {
        string ReadLine();
    }

    public class ConsoleInput : IInput
    {
        public string ReadLine()
        {
            return Console.ReadLine();
        }
    }

    public class StringInput : IInput
    {
        IEnumerable<string> _data;
        IEnumerator<string> _dataEnumerator;

        public StringInput (IEnumerable<string> data)
        {
            _data = data;
            _dataEnumerator = _data.GetEnumerator();
        }

        public string ReadLine()
        {
            _dataEnumerator.MoveNext();
            var retVal = _dataEnumerator.Current;
            return retVal;
        }
    }
}