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


int main() {
    int d;
    cin >> d;
    char* tab = new char[d];
    for(int i = 0; i < d; ++i)
        cin >> tab[i];
    int p = 0, x = 0;
    for(int i = 0; i < d; ++i){
        if (tab[i] == 'U')
            p++;
        else{ 
            p--;
            if(p == -1)
                ++x;
        }
    }
    cout << x;
    return 0;
}