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


int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    int n;
    string hike;
    cin >> n;
    cin >> hike;
    char current;
    int height = 0;
    int valleys = 0;
    bool inValley = false;
    for (int i = 0; i < n; i++) {
        if (hike.at(i) == 'U') {
            height++;
        } else {
            height--;
        }
        if (!inValley && height < 0) {
            valleys++;
            inValley = true;
        }
        if (inValley && height == 0) {
            inValley = false;
        }
    }
    cout << valleys;
    return 0;
}