[1475번] 방 번호

import java.util.Scanner;
 
public class Main {
 
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        
        String a = sc.next();
        int[] b = {0,0,0,0,0,0,0,0,0};
        for(int i=0;i<a.length();i++){
            if(a.charAt(i)=='0') b[0]++;
            else if(a.charAt(i)=='1') b[1]++;
            else if(a.charAt(i)=='2') b[2]++;
            else if(a.charAt(i)=='3') b[3]++;
            else if(a.charAt(i)=='4') b[4]++;
            else if(a.charAt(i)=='5') b[5]++;
            else if(a.charAt(i)=='6' || a.charAt(i)=='9') b[6]++;
            else if(a.charAt(i)=='7') b[7]++;
            else if(a.charAt(i)=='8') b[8]++;
        }
        int c = b[6]/2;
        int d = b[6]%2;
        b[6] = c+d;
        
        int max = 0;
        for(int i=0;i<9;i++){
            if(b[i]>max)
                max = b[i];
        }
        System.out.println(max);
    }
 
 
}