#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;
    std::cin >> n;
    char step;
    int valley = 0, height = 0;
    while(std::cin >> step){
        step=='U'? height++ : height--;
        if(height == 0 && step == 'U') valley++;
    }
    std::cout << valley;
    return 0;
}