如果输入的形状无效，我试图让这段代码重新开始，我将如何解决这个问题？

Question

我正在尝试编写一个程序来计算多个形状的总面积。首先，我找到形状的数量，然后是形状的类型，然后将它们全部加起来。如果输入不正确，我试图让用户重新输入形状类型。我尝试在最后一个 else 中使用 return，但我不断收到错误消息，指出它不在函数内。如果输入无效，我似乎无法弄清楚如何重复 shape_type。

shape_type = input("Type of shape (circle, rectangle, or triangle): ")
    print(shape_type)
    if shape_type == "circle":
        Radius = int(input("Radius: "))
        total_area += (math.pi * Radius**2)
    elif shape_type == "rectangle":
        Length = int(input("Length: "))
        Height = int(input("Height: "))
        total_area += (Length * Height)
    elif shape_type == "triangle":
        Base = int(input("Base: "))
        Height = int(input("Height: "))
        total_area += ((1/2) * Base * Height)
    else:
        print("Shape is Not Valid")

Answer 1

将输入包装在 while True 循环中，只有在输入有效时才跳出循环。

while True:
    shape = input("...")
    if shape in ["circle", "square", "triangle"]:
        break
    else:
        print("Invalid answer, please try again")

# now process the shape which we know is valid

如果输入的形状无效，我试图让这段代码重新开始，我将如何解决这个问题？

I'm trying to get this code to start over if the shape entered is invalid, how would I go about fixing this?

python

recursion

if-statement