import java.io.*;
import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        int n = sc.nextInt();
        char[] values = sc.next().toCharArray();
        ArrayDeque<Character> deq = new ArrayDeque<>();
        deq.add(values[0]);
        int ans = 0;
        for (int i = 1; i < n; i++) {
            if (values[i] == deq.peekLast()) {
                continue;
            }
            if (deq.size() == 1) {
                deq.addLast(values[i]);
                continue;
            }
            char tmp = deq.pollLast();
            if (values[i] == deq.peekLast()) {
                ans++;
                continue;
            }
            deq.addLast(tmp);
            deq.addLast(values[i]);
        }
        if (deq.size() > 0) {
            char first = deq.pollFirst();
            for (char c : deq) {
                if (first != c) {
                    ans++;
                }
            }
            ans++;
        }
        System.out.println(ans);
    }
}

class Scanner {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer("");
    
    public Scanner() throws Exception {
        
    }
    
    public int nextInt() throws Exception {
        return Integer.parseInt(next());
    }
    
    public long nextLong() throws Exception {
        return Long.parseLong(next());
    }
    
    public double nextDouble() throws Exception {
        return Double.parseDouble(next());
    }
    
    public String next() throws Exception {
        if (!st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }
}