#include<iostream>
using namespace std;
int main()
{
	int n;
	cin>>n;
	char s[1000000];
	cin>>s;
	int i,count=0,u=0,d=0;
	for(i=0;i<n;i++)
	{
		if(count==0)
		{
			if(s[i]=='U')
			u++;
			else
			if(s[i]=='D')
			d++;
		}
		if(s[i]=='U')
		count++;
		else
		if(s[i]=='D')
		count--;
		
	}
	//cout<<"Mountain = "<<u<<" valleys = "<<d<<endl;
	cout<<d<<endl;
}