#include <iostream>
#include<string>
using namespace std;


int main() {
    long int n,count,valley = 0,start = 0  ;
    string steps;
    cin>>n;
    cin>>steps;
    for ( long int i = 0;i<n;i++) {
        if ( start == 0 && count == 0 ) start = 1;
        if ( steps[i] == 'U' ) count ++;
        if ( steps[i] == 'D' ) count --;
        if ( start == 0 && count == 0 ) start = 1;
        if ( start == 1 && count == -1 ) start = 2;
        if ( start == 2 && count == 0 && steps[i] == 'U' ) { start = 0 ;  valley ++;}
    }
    cout<<valley<<endl;
    return 0;
}