kingsubin

import java.util.Arrays;
 
public class 전화번호목록 {
    static boolean solution(String[] phone_book) {
        Arrays.sort(phone_book);
        for (int i = 0; i < phone_book.length-1; i++) {
            if (phone_book[i+1].startsWith(phone_book[i])) {
                return false;
            }
        }
        return true;
    }
 
    public static void main(String[] args) {
        String[] phone_book = {"12","123","1235","567","88"};
        boolean solution = solution(phone_book);
        System.out.println(solution);
    }
}