TanSanC

package com.tistory.tansanc;

import java.util.HashSet;

import java.util.Scanner;

public class User {

   public static void main(String[] args) {

       Scanner sc = new Scanner(System.in);

       String[] word = {"기러기", "기차표","스피커"};

       String oldWord = word[

                         (int)(Math.random()*3)  ];

       HashSet<String> hs = new HashSet<String>();

       hs.add(oldWord);

       System.out.println("제시어 : " + oldWord);   

       String newWord = sc.nextLine();

       if( ! hs.add(newWord) )

       {

          System.err.println("중복 발생!");

       }

       if( oldWord.charAt(2) ==

             newWord.charAt(0) )

       {

          System.out.println("OK");

       }

       else

       {

          System.err.println("ERROR");

       }

       while(true)

       {

          oldWord = newWord;

          newWord = sc.nextLine();

          if( ! hs.add(newWord) )

          {

             System.err.println("중복 발생!");

          }

          if( oldWord.charAt(2) ==

                 newWord.charAt(0) )

          {

             System.out.println("OK");

          }

          else

          {

             System.out.println("ERROR");

          }

       }        

   }

}