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


int main() {
	int n;
	cin >> n;
	int sl = 0;
	int pointer = 0;
	int valleys = 0;
	vector<char> hike(n);
	for (int i = 0; i < n; i++) {
		cin >> hike[i];
		if (hike[i] == 'U')
			sl++;
		else if (hike[i] == 'D')
			sl--;
		if( sl == 0)
		{
			if (hike[pointer] == 'D')
				valleys++;
			pointer = i + 1;
		}
	}
	cout << valleys;
	return 0;
}