import java.io.*;
import java.util.*;
import java.util.function.*;
import java.util.stream.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        int n = sc.nextInt();
        Deque<Character> deq = new ArrayDeque<>();
        int ans = 0;
        for (char c : sc.next().toCharArray()) {
            if (deq.size() == 0) {
                deq.add(c);
            } else if (deq.size() == 1) {
                if (deq.peekLast() != c) {
                    deq.add(c);
                }
            } else {
                if (deq.peekLast() != c) {
                    char x = deq.pollLast();
                    if (deq.peekLast() == c) {
                        ans++;
                    } else {
                        deq.add(x);
                        deq.add(c);
                    }
                }
            }
        }
        ans += deq.size();
        char first = deq.peekFirst();
        while (deq.size() > 0) {
            char x = deq.poll();
            if (x == first) {
                ans--;
            }
        }
        System.out.println(ans + 1);
    }
}
class Scanner {
    BufferedReader br;
    StringTokenizer st = new StringTokenizer("");
    StringBuilder sb = new StringBuilder();
    
    public Scanner() {
        try {
            br = new BufferedReader(new InputStreamReader(System.in));
        } catch (Exception e) {
            
        }
    }
    
    public int nextInt() {
        return Integer.parseInt(next());
    }
    
    public long nextLong() {
        return Long.parseLong(next());
    }
    
    public double nextDouble() {
        return Double.parseDouble(next());
    }
    
    public String next() {
        try {
            while (!st.hasMoreTokens()) {
                st = new StringTokenizer(br.readLine());
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            return st.nextToken();
        }
    }
    
}