import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.StringTokenizer;

public class Main {
    public static void main(String[] args){
        PrintWriter out = new PrintWriter(System.out);
        FastScanner sc = new FastScanner();

        String S = sc.nextToken();
        int N = S.length();

        String prev = "";
        int ans = 0;
        int i = 0;

        int n = 1;
        while (i+n <= N) {
            String s = S.substring(i, i+n);
            if (s.equals(prev) == false) {
                prev = s;
                ans++;
                i = i + n;
                n = 1;
            } else {
                n++;
            }
        }


        out.println(ans);
        out.flush();
    }

    public static class FastScanner {
        BufferedReader br;
        StringTokenizer st;

        public FastScanner(String s) {
            try {
                br = new BufferedReader(new FileReader(s));
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            }
        }

        public FastScanner() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        String nextToken() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt() {
            return Integer.parseInt(nextToken());
        }

        long nextLong() {
            return Long.parseLong(nextToken());
        }

        double nextDouble() {
            return Double.parseDouble(nextToken());
        }

        int[] nextIntArray(int N) {
            int a[] = new int[N];
            for (int i=0;i<N;i++) {
                a[i] = this.nextInt();
            }

            return a;
        }

        long[] nextLongArray(int N) {
            long a[] = new long[N];
            for (int i=0;i<N;i++) {
                a[i] = this.nextLong();
            }

            return a;
        }

        double[] nextDoubleArray(int N) {
            double a[] = new double[N];
            for (int i=0;i<N;i++) {
                a[i] = this.nextDouble();
            }

            return a;
        }

        String[] nextTokenArray(int N) {
            String a[] = new String[N];
            for (int i=0;i<N;i++) {
                a[i] = this.nextToken();
            }

            return a;
        }
    }
}