编写程序相加两个分数，并将它们的和以化简后的分数形式表现出来。程序使用类Fraction来存放分数的分子和分母，具有方法Reduce来化简结果。-Program to add two scores, and they and the simplification of the fraction form. Procedures for the use of class Fraction to store the fractional molecule and denominator, with