/*
	https://www.hackerrank.com/contests/rookierank/challenges/counting-valleys
*/

#include <iostream>
#include <vector>
#include <algorithm>
#include <iterator>

using namespace std;


bool isZero(int test){return test==0;}

int main()
{
	int n;
	cin >> n;
	
	// The Us and Ds.
	string journey;
	cin >> journey;

	/*
		Using the input, create a vector that 
		functions as the function D(t), 
		where D is the depth and t is
		the time-step.
	*/
	
	vector<int> depth;
	int totalDepth = 0;
	depth.push_back(totalDepth);
	for (auto iter = journey.begin(); iter < journey.end(); iter++)
	{
		char mander = *iter;

		if (mander == 'D')
			totalDepth--;
		else if (mander == 'U')
			totalDepth++;
		depth.push_back(totalDepth);
	}

	/*
		The number of valleys will be the times that D(t)
		dips below 0 and then returns.

		D(t) is a continuous function,
		so any region between t1 and t2
		such that D(t1)=0 and D(t2)=0 is
		either a hill or a valley,
		if there is no point t3 in between t1 and t2
		such D(t3)=0.
		
		To see if the region is a valley, 
		evaluate D at an arbitrary point in between t1 and t2.
		If that point is negative, 
		the region is a valley.
	*/

	// Find all points such that D(t)==0.
	// http://stackoverflow.com/a/25846323/5415895
	vector<int> zeros;
	vector<int>::iterator iter = depth.begin();
	while ((iter = find_if(iter, depth.end(), isZero)) != depth.end())
	{
    	// Add the distance to iter from the beginning of the vector.
		int dist = distance(depth.begin(), iter);
		zeros.push_back(dist);

    	iter++;
	}

	int valleys = 0;
	for (int i = 0; i < zeros.size()-1; i++)
	{
		// Get a point between i and i+1.
		int between = (zeros[i] + zeros[i+1])/2;
		if (depth[between] < 0)
			valleys++;
	}

	cout << valleys;

	return 0;
}