#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 stepCount = 0;
    string steps;    
    cin >> stepCount >> steps;
    
    int valley = 0;  
    int totalClimb = 0;    
    bool isValley = false;
    
    for(int i = 0; i < steps.length(); i++ )
    {
        if(steps[i] == 'U')
        {
            totalClimb++;   
        }
        
        if(steps[i] == 'D')
        {
            if(totalClimb == 0 && isValley == 0)
            {
                isValley = true;   
            }
            totalClimb--;
        }

        if(totalClimb == 0 && isValley)
        {
            valley++;
            isValley = false;
        }
    }
    
    cout << valley;
    
    return 0;
}