백준 3단계 no.14

import java.util.*;

public class Main{
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        
        int n = sc.nextInt();
        int sub = n;
        int count = 0;
        
        do { 
            int a = sub/10;
            int b = sub%10;
            int c = (a+b)%10;
            
            sub = 10*b+c;
            
            count++;
        } while (sub != n);
        
        System.out.print(count);
    }
}