#include <iostream>
#include <stdio.h>
#include <bits/stdc++.h>

#define f first
#define s second

using namespace std;
int step = 0;
int valley = 0;

int main(){
    int n;
    cin >> n;
    for(int counter = 0; counter < n; counter++)
    {
        char x;
        scanf(" %c", &x);
        int y = (x == 'U' ? 1: -1);
        if(step == 0 && step + y < 0)
            valley++;
        step += y;
    }
    cout << valley << endl;
    return 0;
}