#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 numSteps;
    string path;
    cin >> numSteps;
    cin >> path;
    int altitude = 0;
    int valleys = 0;
    bool isValley = false;
    for(int i =0; i < numSteps;){
        isValley = false;
        if(path[i] == 'D'){
            while(path[i] == 'D' && i < numSteps){
                i++;
                altitude--;
               // cout << "D";
            }
            for(;altitude < 0 && i < numSteps;i++){
                isValley = true;
                if(path[i] =='D'){
                    altitude--;
                    //cout << "d";
                }
                else{
                    altitude++;
                    //cout << "u";
                }
            }
            if(isValley) valleys++;
        }
        else {
            //cout << "U";
            altitude++;
            i++;
        }
    }
    cout << valleys;
    return 0;
}