输入某年某月某日，返回这一天是星期几。程序具有容错性和健壮性。-Enter a certain period of a particular day, the return day of the week. The program has the fault tolerance and robustness.

中缀多项式计算器，能算浮点数的多位运算，界面友好，有一定容错能力-Polynomial calculator infix can count the floating-point number operation, friendly interface, some fault tolerance