#include <iostream>
#include <string>
using namespace std;

int main(){
    int n;
	int current_level = 0;
	int valleys = 0;
	int mountains = 0;
	string steps;
	
	
	cin >> n >> steps;
	
	for(int i = 0; i < n; ++i){
		if (steps[i] == 'U'){
			++current_level;
			if (current_level == 0){
				//If we stepped up and are now at 0, that was the end of a valley
				++valleys;
			}
		}
		else if (steps[i] == 'D'){
			--current_level;
			if (current_level == 0){
				//If we stepped down and are now at 0, that was the end of a mountain
				++mountains;
			}
		}
	}
	
	cout << valleys; 
    return 0;
}