180403_2810_컵홀더

	//https://www.acmicpc.net/problem/2810 #include <iostream>
	using namespace std;
	int main(){
	int N;
	char chair[50];
	cin >> N;
	int ans=1;
	bool chk=0;
	for(int i=0; i<N; i++) {
	cin >> chair[i];
	if(chair[i]=='S') ans++;
	if(chair[i]=='L'){
	if(!chk) chk=1;
	else {
	ans++;
	chk=0;
	}
	}
	}
	if(ans<N) cout << ans;
	else cout << N;
	}