using System;
using System.Collections.Generic;
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 */
        string n = Console.ReadLine();
        char[] arr = Console.ReadLine().ToCharArray();
        Console.WriteLine(CountValleys(arr));
    }
    
    static int CountValleys(char[] arr){
        int valleys = 0;
        int position = 0;
        bool inValley = false;
        foreach(char item in arr){
            
            position = item == 'U' ? position += 1 : position -= 1;
            if (position == -1 && !inValley){
                inValley = true;
                valleys += 1;
            }
            else if (position == 0 && inValley){
                inValley = false;
            }
        }
        return valleys;
    }
}