[백준] 1110 더하기 사이클 (Java)

 

단계별로 풀기에서 단계4까지 중 가장 어려웠던 문제.

/*
 * Author : Jeonghun Cho
 * Date : December 3, 2019
 * https://www.acmicpc.net/problem/1110
 */
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
 
public class Main {
 
    public static void main(String[] args) throws IOException {
        // TODO Auto-generated method stub
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
        String str = br.readLine();
        if(str.length() == 1) {
            str = "0"+str;
        }
        String answer = str; 
        int cnt = 0;
        while(true) {
            int tens = str.charAt(0)-48; 
            int units = str.charAt(1)-48; 
            int result = tens+units; 
            if(result >= 10) {
                result %= 10; 
            }
            str = units+""+result; 
            cnt++; 
            if(str.equals(answer)) {
                bw.write(cnt+"\n");
                bw.flush();
                break;
            }
        }
    }
}