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

class Main{
  public static void main(String[] args) throws IOException{

    int bit=8;
    BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
    long n=Long.parseLong(br.readLine());

    String buf=String.valueOf(n);
    int count=buf.length()-2;
    
    if(bit>=count){
      int result=bit-count;
      System.out.println(result);
    }else{
      int result=count-bit;
      System.out.println(result);
    }
  }
}