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


int main() {
    string s;
    int sum = 0;
    int cnt = 0;
    bool inValley = false;
    
    int n;
    cin >> n;
    cin >> s;
    for (int i = 0; i < s.size(); i++) {
        if (s[i] == 'U')
            sum++;
        else sum--;
        
        if (sum < 0 && !inValley) {
            cnt++;
            inValley = true;
        } else if (sum >= 0)
            inValley = false;
    }
    
    cout << cnt;
    return 0;
}