#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 n;
    char ch[1000009];
    scanf("%d",&n);
    cin>>ch;
    int ans=0;
    int cur=0;
    int flag=0;
    for(int i=0;i<n;i++){
        if(ch[i]=='U'){
            cur++;
        }
        else{
            cur--;
        }
        if(cur<0){
            flag=1;
        }
        if(flag==1 && cur==0){
            flag=0;
            ans++;
        }
    }
    cout<<ans<<endl;
    return 0;
}