chiffre manquant sudoku

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

class Solution {

    public static void main(String args[]) {
        Scanner in = new Scanner(System.in);
        String s = in.nextLine();
        boolean[] tab = {false, false, false, false, false, false, false, false, false, false};
        for(char c : s.toCharArray())
        {
            if(Character.isDigit(c))
                tab[c-'0'] = true;
        }
        for(int i = 1; i <= 9; i++)
            if(!tab[i])
                System.out.println(i);
    }
}