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


int main() {
    int height = 0;
    int valleys = 0;
    char step;
    int n;
    cin >> n;
    
    for (int i = 0; i<n; i++) {
        cin >> step;
        if (step == 'U'){
            height++;
            if (height == 0) {
               valleys++;
            }
        }
        else {
            height--;
        }
        
    }
    
    cout << valleys;
    return 0;
}