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


int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */     int n = 0;
    string s;
    cin >> n;
    cin >> s;
    
    int status = 0;
    int valleys = 0;
    for(int i = 0; i < n; i++) {
        if(s[i] == 'U' && status == -1) {
            valleys++;
        }
        if(s[i] == 'U') {
            status++;
        } else {
            status--;
        }
        
        
    }
    cout << valleys;
    return 0;
}