模拟XP自带计算器功能。 程序应按用户输入的要求进行相应的运算，并输出结果。在用户要求终止程序运行前，上述过程是重复的。-First of all, want to request the user to enter their own calculations in one type of +,-,*,/, enter two numbers program requirements shall be entered by the user corresponding operatio