백준 1110 - 더하기 사이클

#include <iostream>
#include <stdio.h>
 
using namespace std;
 
int main(void) {
    int ref, num, cycle=0;
    cin >> num;
    ref = num;
    
    while(true) {
        if(num < 10) {
            num = num*10 + num;
        } else {
            num = (num%10)*10 + (num%10 + num/10)%10;
        }
        cycle++;
        
        if(num == ref)
            break;
    }
    
    cout << cycle << endl;
    
    return 0;
}