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


int main() {
    size_t length;
	std::cin >> length;

	int elev = 0;
	size_t valies = 0;
	bool valey_started = false;
	std::string symbols;
	std::cin >> symbols;
	for (int i = 0; i < symbols.size (); i++)
	{
		char step = symbols [i];

		if (step == 'U')
			elev++;
		else
			elev--;

		if (elev == 0 && valey_started)
		{
			valey_started = false;
			valies++;
		}
		else if (elev < 0 && valey_started == false)
			valey_started = true;
	}

	std::cout << valies;
    
    return 0;
}