1.实现分数运算符重载； 2.实现分数的输入； 3.用两种化简方法实现分数的化简，比较两种分数化简方法的效率； 4.实现分数的输出。-1. fractional operator overloading score 2 for input 3. simplification achieved by simple fraction of the two methods, the efficiency of the simple method of comparing two