#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;
    cin >> n;
    string hike;
    cin >> hike;
    
    int fromSeaLevel = 0;
    int valleyCount = 0;
    bool inValley = false;
    for (int i = 0; i < n; i++) {
        if (hike[i] == 'U') {
            fromSeaLevel++;
        } else {
            fromSeaLevel--;
        }
        
        if (fromSeaLevel < 0) {
            inValley = true;
        }
        
        if (inValley && fromSeaLevel == 0) {
            valleyCount++;
            inValley = false;
        }
    }
    
    cout << valleyCount << endl;
    
    return 0;
}