class Assignment4{
    public static void main(String[] args) {

        System.out.println(biggestDigit(239296));
    }

    static int biggestDigit(int num) {
        if(num < 10)return num;

        int digit1 = num%10;
        int digit2 = (num/10)%10;
        int newNum = ((num/100)*10);

        return biggestDigit(newNum+Math.max(digit1, digit2));
    }

}