#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {
    int n , level=0 , valley=0 , num=0;
    string steps;
    cin >> n >> steps;
    for(int i=0 ; i<n ; i++){
        if(steps[i]=='U'){level++;}
        else{level--;}
        if(level<0){
            if(valley!=1){
                valley=1;
                num++;
            }//if
        }//if
        else{valley=0;}
    }//for
    cout << num <<endl;  
    return 0;
}