using System;
using System.Linq;
class Solution
{

    static void Main(String[] args)
    {
        Console.ReadLine();

        var values = Console.ReadLine().Select(z => z == 'U' ? 1 : -1);

        var sum = 0;
        var result = 0;
        var isGoToValley = false;

        foreach (var value in values)
        {
            if (sum == 0 && value == -1)
            {
                isGoToValley = true;
            }
            sum += value;

            if (sum == 0)
            {
                if (isGoToValley)
                {
                    result++;
                    isGoToValley = false;
                }
            }
        }

        Console.WriteLine(result);
    }
}