read -p "是否開始遊戲(y/n)" a;
while [ $a == y ] ;do
        read -p "
* * * * * * *
*  石頭(0)  *
*  剪刀(1)  *
*  布(2)    *
*  退出(3)  *
* * * * * * *
" b;
c=`echo $[$RANDOM%3]`;
  if [ $b -ge 0 ] ;then
        if [ $b -le 3 ] ;then
            if [ $b == $c ] ;then
                echo "玩家：$b";
                echo "電腦：$c";
                echo "平局！";
                elif [ $b == 3 ] ;then
                echo "退出遊戲！";
          else
                if [ $b == 1 -a $c == 2 ] || [ $b == 0 -a $c == 1 ] || [ $b == 2 -a $c == 0 ] ;then
                        echo "玩家：$b";
                        echo "電腦：$c";
                        echo "玩家：勝！";
                else
                        echo "玩家：$b";
                        echo "電腦：$c";
                        echo "電腦：勝！";
                fi
           fi
                 if [ $b == 3 ] ;then
                break;
                 fi
        else
                echo "請輸入正確選項！"
        fi
    else
        echo "輸入正確選項！"   
    fi
done
   									#剛剛學習，請多指教！