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


int main() {
    int n;
	int lv = 0;
	char ch;
	bool valley;
	int num = 0;
	
	//Input of number of steps
		std::cin >> n;
		while (n--){
			std::cin >> ch;
		if (ch == 'U'){
				lv++;
			}
		else{
				lv--;
			}
		if (lv < 0){
			valley = true;
		}
		else{
			valley = false;
		}

		if (lv == -1 && valley && ch == 'D'){
			num++;
		}
			

	}
	std::cout << num << endl;

	std::cin.get();
	std::cin.ignore();

	return 0;
}