#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {
    int size;
    cin >> size;
    int alt = 0;
    int lastAlt = 0;
    int out = 0;
    
    string in;
    cin >> in;
    
    for(int i = 0; i < size; i++){
        
        //changes altitude
        if(in.at(i)=='U'){
            alt++;
        }else{
            alt--;
        }
        
        //checks for vally
        if(lastAlt >= 0 && alt < 0){
            
            out++;
            
        }
        
        lastAlt = alt;
        
    }
    
    cout << out;
    
    
    return 0;
}