#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;
    cin >> n;
    int height = 0;
    int count = 0;
    bool begin_valley = false;
    for (int i = 0; i < n; ++i) {
        char c;
        cin >> c;
        
        if (c == 'U') {
            ++height;
        } else {
            --height;
        }
        if (height < 0) {
            begin_valley = true;
        }
        if (begin_valley && height == 0) {
            begin_valley = false;
            ++count;
        }
    }
    cout << count;
    return 0;
}