#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 */   
    vector<char> c;
    int n;
    cin>>n;
    int sea_level=0,valley=0,mountain=0,no_valley=0,no_mountain=0;
    for(int i=0;i<n;i++)
     {   char d;
      cin>>d;
            c.push_back(d);
     }
    vector<char>:: iterator v;
    v=c.begin();
    while(v!=c.end())
        {
        if(*v=='U')
            sea_level++;
        else
            sea_level--;
        if(sea_level<0)
            valley++;
        if(sea_level>0)
            mountain++;
        if(sea_level==0)
        {if(abs(valley)>mountain)
            no_valley++;;
            if(mountain>abs(valley))
            no_mountain++;
            valley=0;
         mountain=0;}
    v++;}
    cout<<no_valley;
    return 0;
}