设计一个点类(Point)和一个圆类(Circle)，输入点坐标和圆心坐标及半径，判断点和圆的关系(点在圆内，点在圆上，点在圆外)

设计一个点类(Point)和一个圆类(Circle)可以使用Python来实现，这里是一个简单的示例：

class Point:
    def __init__(self, x, y):
        self.x = x
        self.y = y

class Circle:
    def __init__(self, center_x, center_y, radius):
        self.center = Point(center_x, center_y)
        self.radius = radius

    def is_point_in_circle(self, point):
        distance = ((point.x - self.center.x)**2 + (point.y - self.center.y)**2)**0.5
        return distance < self.radius  # 点在圆内
        return distance == self.radius  # 点在圆上
        return distance > self.radius  # 点在圆外

# 示例使用
circle = Circle(0, 0, 5)
point = Point(3, 4)

if circle.is_point_in_circle(point):
    print("点在圆内")
elif circle.is_point_on_circle(point):
    print("点在圆上")
else:
    print("点在圆外")