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


int main() {
  char c;
	int n=0, lvl=0, count =0;
	bool valley;
	cin>>n;
	while(n--)
	{
	   cin>>c;
	   if(c=='U')
		lvl++;
	   else
		lvl--;
	   if(lvl <0)
	   {
		valley = true;
	   }
	   else if(valley)
	   {
		count++;
		valley = false;
	   }
	}
	cout<<count;
	return 0;
}