1、编写一个Java应用程序。用户从键盘输入一个1～99999之间的整数，程序将判断这个数是几位数，并判断这个数是否是回文数。回文数是指将该数含有的数字逆序排列后得到的数和原数相同，如12121和3223都是回文数。

2、编写一个Java应用程序，该程序中有一个Rational(有理数)类，具体要求如下：

?Rational类有两个int型的成员变量，名字分别为numerator(分子)和denominator(分母)。

?提供Rational add(Rational r)方法，即有理数调用该方法与参数指定的有理数做加法运算，并返回一个Rational对象。

?提供Rational sub(Rational r)方法，即有理数调用该方法与参数指定的有理数做减法运算，并返回一个Rational对象。

?提供Rational muti(Rational r)方法，即有理数调用该方法与参数指定的有理数做乘法

-1, write a Java application. The user from the keyboard to enter a whole number between 1 ~ 99999, Cheng

Order to determine this number is a few numbers, and determine whether this number is a palindrome. Palindrome refers to the

Reverse order with the number of figures obtained by the same number and the original number, such as 12121 and 3223 are palindromic

Number.

2, write a Java application program that has a Rational (rational) class, specific to

Requirements are as follows:

? Rational class has two member variables of type int, the name was numerator (numerator) and

denominator (denominator).

? Provides Rational add (Rational r) method, that is rational to call the specified method and parameters

Rational to do addition operations, and returns a Rational object.

? Provides Rational sub (Rational r) method, that is rational to call the specified method and parameters

Rational to do subtraction, and returns a Rational object.

? Provides Rational muti (Ratio