using System;
using System.Collections.Generic;
using System.IO;
class Solution {
    static void Main(String[] args) {
        Console.ReadLine();
        var s = Console.ReadLine();
        var a = new int[s.Length];

        var c = s[0];
        var sum = 1;
        var pos = 0;
        for (var i = 1; i < s.Length; i++)
        {
            if (s[i] == c)
            {
                sum++;
                if (i == s.Length - 1)
                {
                    if (c == 'D') sum = -sum;
                    if (pos > 0) sum += a[pos - 1];
                    a[pos] = sum;
                }
                continue;
            }

            if (c == 'D') sum = -sum;
            if (pos > 0) sum += a[pos - 1];

            a[pos] = sum;
            sum = 1;
            c = s[i];
            pos++;
        }

        var res = 0;

        for (var i = 1; i < pos + 1; i++)
        {
            if (a[i] >= 0 && a[i - 1] < 0) res++;
        }

        Console.WriteLine(res);
    }
}