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


int main() {
    int n, height = 0, flag = 0, valleyCounter = 0;
    cin >> n;
    char step;
    for(int i=0; i<n+1; i++){
        scanf("%c", &step);
        //printf("%c", step);
        if(step == 'U'){
            height++;
            //printf("%d", height);
        }
        if(step == 'D'){
            height--;
            //printf("%d", height);
        }
        if(height == -1){
            flag = 1;
        }
        if(height == 0 && flag == 1){
            valleyCounter++;
            flag = 0;
        }
    }
    printf("%d", valleyCounter);
    return 0;
}