#include<bits/stdc++.h>
#include<atcoder/all>
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;
using namespace atcoder;
typedef long long ll;
typedef vector<int> vi;
typedef vector<long long> vl;
typedef vector<vector<int>> vvi;
typedef vector<vector<long long>> vvl;
typedef long double ld;
typedef pair<int, int> P;

ostream& operator<<(ostream& os, const modint& a) {os << a.val(); return os;}
template <int m> ostream& operator<<(ostream& os, const static_modint<m>& a) {os << a.val(); return os;}
template <int m> ostream& operator<<(ostream& os, const dynamic_modint<m>& a) {os << a.val(); return os;}
template<typename T> istream& operator>>(istream& is, vector<T>& v){int n = v.size(); assert(n > 0); rep(i, n) is >> v[i]; return is;}
template<typename U, typename T> ostream& operator<<(ostream& os, const pair<U, T>& p){os << p.first << ' ' << p.second; return os;}
template<typename T> ostream& operator<<(ostream& os, const vector<T>& v){int n = v.size(); rep(i, n) os << v[i] << (i == n - 1 ? "\n" : " "); return os;}
template<typename T> ostream& operator<<(ostream& os, const vector<vector<T>>& v){int n = v.size(); rep(i, n) os << v[i] << (i == n - 1 ? "\n" : ""); return os;}
template<typename T> ostream& operator<<(ostream& os, const set<T>& se){for(T x : se) os << x << " "; os << "\n"; return os;}
template<typename T> ostream& operator<<(ostream& os, const unordered_set<T>& se){for(T x : se) os << x << " "; os << "\n"; return os;}
template<typename S, auto op, auto e> ostream& operator<<(ostream& os, const atcoder::segtree<S, op, e>& seg){int n = seg.max_right(0, [](S){return true;}); rep(i, n) os << seg.get(i) << (i == n - 1 ? "\n" : " "); return os;}
template<typename S, auto op, auto e, typename F, auto mapping, auto composition, auto id> ostream& operator<<(ostream& os, const atcoder::lazy_segtree<S, op, e, F, mapping, composition, id>& seg){int n = seg.max_right(0, [](S){return true;}); rep(i, n) os << seg.get(i) << (i == n - 1 ? "\n" : " "); return os;}

template<typename T> void chmin(T& a, T b){a = min(a, b);}
template<typename T> void chmax(T& a, T b){a = max(a, b);}

// thanks for snuke-san's blog
// https://snuke.hatenablog.com/entry/2014/12/02/235837
vector<int> manacher(vector<int>& s){
	int n = s.size();
	vector<int> res(n);
	int i = 0, j = 0;
	while(i < n){
		while(i - j >= 0 && i + j < n && s[i-j] == s[i+j]) ++j;
		res[i] = j;
		int k = 1;
		while(i - k >= 0 && k + res[i-k] < j) res[i+k] = res[i-k], ++k;
		i += k; j -= k;
	}
	return res;
}

vector<int> manacher(string& s){
	vector<int> s_converted;
	for(char c : s) s_converted.push_back(c);
	return manacher(s_converted);
}


// https://atcoder.jp/contests/abc259/editorial/4283
vector<pair<char, int>> RLE(vector<int>& s){
	vector<pair<char, int>> res;
	int cnt = 1;
	for(int i = 1; i < (int)s.size(); i++){
		if(s[i] != s[i-1]){
			res.push_back({s[i-1], cnt});
			cnt = 0;
		}
		cnt++;
	}
	res.push_back({s.back(), cnt});
	return res;
}

vector<pair<char, int>> RLE(string& s){
	vector<int> s_converted;
	for(char c : s) s_converted.push_back(c);
	return RLE(s_converted);
}

int main(){
	int n;
	cin >> n;
	string s;
	cin >> s;
	auto rle = RLE(s);
	cout << rle.size() << "\n";
	return 0;
}