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


int main() {
    int n,sea=0,valley =0;
    bool start = false;
    string s;
    cin>>n;
    cin>>s;
    for (int i =0;i<n;i++){
        if (s[i] == 'U') sea++;
        else sea--;
        if (start && sea==0) start = false;
        //cout <<sea<<" "<<valley<<" ";
        if (!start && sea<0) {valley++;start = true;}
        
    }
    cout<<valley;
    return 0;
}