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


int main() {
    int elevation = 0;
    int valleys = 0;
    int n;
    std::cin >> n;
    char step;
    while (n--) {
        std::cin >> step;
        int old_elevation = elevation;
        elevation += (step == 'U' ? 1 : -1);
        if (elevation == -1 && old_elevation == 0) {
            ++valleys;
        }
    }
    std::cout << valleys << std::endl;
    return 0;
}