Question

这是我的代码，我正在尝试添加递归，因此当用户输入一个小于 0 的数字时，它不仅会说无效输入，还会显示原始提示，让他们尝试另一个数字。我也在尝试将我的 for 循环更改为 while 循环。有什么帮助吗？

space = '\t'
star = '*'
size = int(input("Enter the height of the pattern (must be greater than 0): "))

if size <= 0 :
    print("Invalid Entry!\n")

for i in range(0, size) :
    star_count = 2 * i - 1

    line = space * (size - i - 1)

    if i == 0 :
        line += "1"
    else :
        line += str(2 * i) + space

    line += (star + space) * star_count

    if i > 0 :
        line += str(2 * i + 1)

    print(line)

输出应该是这样的

                1
            2   *   3
        4   *   *   *   5
    6   *   *   *   *   *   7
8   *   *   *   *   *   *   *   9

Answer 1

如果大小不大于 0，您可以添加一个条件来重复输入循环

space = '\t'
star = '*'

size = -1
while size <= 0:
    size = int(input("Enter the height of the pattern (must be greater than 0): "))
    if size <= 0 :
        print("Invalid Entry!\n")

for i in range(0, size) :
    star_count = 2 * i - 1

    line = space * (size - i - 1)

    if i == 0 :
        line += "1"
    else :
        line += str(2 * i) + space

    line += (star + space) * star_count

    if i > 0 :
        line += str(2 * i + 1)

    print(line)

所以输出是

Enter the height of the pattern (must be greater than 0):  -2
Invalid Entry!

Enter the height of the pattern (must be greater than 0):  0
Invalid Entry!

Enter the height of the pattern (must be greater than 0):  3
        1
    2   *   3
4   *   *   *   5

Answer 2

for 循环有什么问题？

space = '\t'
star = '*'
while 1:
    size = int(input("Enter the height of the pattern (must be greater than 0): "))
    if size > 0:
        break
    print("Invalid Entry!")
    print("Please Try again.")

i = 0
while i < size:
    star_count = 2 * i - 1

    line = space * (size - i - 1)

    if i == 0 :
        line += "1"
    else :
        line += str(2 * i) + space

    line += (star + space) * star_count

    if i > 0 :
        line += str(2 * i + 1)
    i += 1

    print(line)

Answer 3

此代码的限制是您必须始终输入 3 才能获得打算根据您的查询获得的答案

space = '\t'
star = '*'
size = int(input("Enter the height of the pattern (must be greater than 0): "))

while size <= 0 :
    print("Invalid Entry!\n")
    size = int(input("Enter the height of the pattern (must be greater than 0): "))

for i in range(0, size) :
    star_count = 2 * i - 1

    line = space * (size - i - 1)
    if i == 0 :
        line += "1"
    else :
        line += str(2 * i) + space
    line += (star + space) * star_count
    if i > 0 :
        line += str(2 * i + 1)
    print(line)

添加递归并将 for 循环转换为 while 循环

3 个答案: