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


int main() {
    int n, valleys = 0;
    cin >> n;
    char step;
    for(int i = 0, level = 0; i < n; i++) {
        cin >> step;
        if(step == 'U') {
            level++;
            if(level == 0) {
                valleys++;
            }
        } else {
            level--;
        }
    }
    cout << valleys << endl;
    return 0;
}