# 实现 Circle 类... import math class Circle(): radius = float(0) def __init__(self, radius:float) -> None: self.radius = radius def get_peimeter(self) -> float: return math.pi * self.radius * 2 def get_area(self) -> float: return math.pi * (self.radius ** 2) def __str__(self) -> str: return f"radius: {self.radius}\npeimeter: {self.get_peimeter()}\narea: {self.get_area()}\n" def main() -> int: cir1 = Circle(3.0) # print(str(cir1)) print(f"cir1: peimeter: {cir1.get_peimeter()}") print(f"cir1: narea: {cir1.get_area()}") return 0 if __name__ == "__main__": main()