#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, slevel=0, valeys=0;
    cin >> n;
    
    for(int j = 0; j < n; j++){
        char step;
        cin >> step;
        if(step == 'U'){
            if(slevel == -1){
                valeys++;
            }
            slevel++;
        }else{
            slevel--;
        }
    }
    cout << valeys;
    return 0;
}