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


int main() {
    int n;
    cin >> n;
    cin.ignore(numeric_limits<streamsize>::max(), '\n');
    string steps = "";
    getline(cin, steps);
    
    int numVals = 0;
    int valley = 0;
    int currentLvl = 0;
    for (char& c : steps){
       if (c == 'U'){
           currentLvl++;
       }else{
           currentLvl--;
       } 
       if (currentLvl == 0 && valley == 1){
           //Just exited valley
           numVals++;
           valley = 0;
       }else if (currentLvl < 0 && valley == 0){
           // Just entered valley
           valley = 1;
       }
       
    }
    cout << numVals;
    return 0;
}