using System;
using System.Collections;
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 n = Convert.ToInt32(Console.ReadLine());
        char[] steps = Console.ReadLine().ToCharArray();
        
        if (n <= 0)
            return;
        
        int prevStep = 0;
        int valleyCount = 0;
        
        foreach(char step in steps) {
        
            if (step == 'D')
                {
               prevStep = prevStep - 1;
            } else {
                prevStep = prevStep + 1;

                if (prevStep == 0)
                    valleyCount++;
            }
        }
        
        Console.Write(valleyCount);
    }
}