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


int main() {
    int n;
    cin >> n;
    
    int nvalleys = 0;
    int height = 0;
    char step;
    for (int i = 0; i < n; i++) {
        cin >> step;
        
        if (step == 'U') {
            height++;
            if (height == 0) {
                nvalleys++;
            }
        } else if (step == 'D') {
            height--;
        } else {
            cerr << "Invalid step " << step << endl;
            exit(1);
        }
    }
    
    cout << nvalleys;
    return 0;
}