#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 */   
    char input_string[1000000];
    char hike_status='S';
    int count=0, sea_level=0, N;
    cin>>N;
    cin>>input_string;
    for (int i = 0; i<=N-1; i++){
        if(input_string[i]=='U') sea_level++;
        if(input_string[i]=='D') sea_level--;
        if(sea_level==0 && hike_status=='V'){
            count++;
        }
        if(sea_level<0) hike_status = 'V';
        if(sea_level>0) hike_status = 'M';
        if(sea_level==0) hike_status = 'S';
    }
    cout<<count;
    return 0;
}