#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 steps;
    cin.ignore();
    getline(cin,steps);
    int height = 0,ValleyFlag =0, ValleyCount =0;
    for(int i =0;i<steps.length();i++)
    {
        if(steps[i] == 'U')
        {
            if(height == -1 && ValleyFlag == 1)
            {
                ValleyCount++;
                ValleyFlag = 0;
            }
            height++;
        }
        if(steps[i] == 'D')
            {
            if(height == 0)
                ValleyFlag = 1;
            
            height--;
        }
    }
    cout<<ValleyCount;
    return 0;
}