#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 a[1000000] ;
    char ch;
    long int i,n,val = 0,c = 0, tog = 0,f = 0;
    cin>>n;
   
    for (i=0;i<n;i++){
        cin>>ch;
        if (ch == 'U')
            { a[i] = ++val;  }
        else if (ch == 'D'){a[i] = --val; }

        if (val == -1  && ch == 'D' && !tog ) {tog = 1;}
        
        else if (val == 0  &&  tog && ch == 'U') {c++; tog = 0;}
 
        
        
        
        
        
        
        
    }
    printf("%d",c);
    return 0;
}