我知道在此网站上曾有人问过这个问题,但是我无法理解给出的答案(我仍然很新),因此我将尝试再次询问。我的任务是编写使用10位数字的电话号码(XXX-XXX-XXXX)并将任何字母(即800-FLO-WERS)转换为数字的代码。我为此动了脑筋,真的可以使用一些帮助/解释。在我正在上的课中(使用出色的“ Tony Gaddis撰写的第4版Python入门”),我不能使用我们没有涵盖的概念(如字典),但可以使用列表/元组。 ve提出如下:
def main():
try:
user_number = str(input('Enter a phone number (XXX-XXX-XXXX): ')).upper()
converted_number = check_number(user_number)
print('The phone number is:',converted_number
except Exception as err:
print(err)
def check_number(user_number):
try:
for char in user_number:
if char.isalpha():
result = convert_to_num(char)
return result
else:
return char
return converted_number
except Exception as err:
print(err)
def convert_to_num(char):
if char in ['A','B','C']:
char = 2
elif char in ['D','E','F']:
char = 3
elif char in ['G','H','I']:
char = 4
elif char in ['J','K','L']:
char = 5
elif char in ['M','N','O']:
char = 6
elif char in ['P','Q','R','S']:
char = 7
elif char in ['T','U','V']:
char = 8
elif char in ['W','X','Y','Z']:
char = 9
return char
main()
很明显,我不确定如何存储转换后的字母到数字(考虑通过索引来实现,但是也不能完全做到这一点)。我并不想找任何人为我做我的工作,但是详细说明我做错的事情会很可爱。
答案 0 :(得分:0)
return
的目的是返回到调用它的函数。因为for char in user_number:
if char.isalpha():
result = convert_to_num(char)
return result
else:
return char
return converted_number
在循环内。它将在第一次迭代中退出该函数。
join()
仅使用列表来存储转换后的值,然后在循环后使用def main():
try:
user_number = str(input('Enter a phone number (XXX-XXX-XXXX): ')).upper()
converted_number = check_number(user_number)
print('The phone number is:',converted_number)
except Exception as err:
print(err)
def check_number(user_number):
try:
r = []
for char in user_number:
if char.isalpha():
result = convert_to_num(char)
r.append(str(result))
else:
r.append(char)
return "".join(r)
except Exception as err:
print(err)
def convert_to_num(char):
if char in ['A','B','C']:
char = 2
elif char in ['D','E','F']:
char = 3
elif char in ['G','H','I']:
char = 4
elif char in ['J','K','L']:
char = 5
elif char in ['M','N','O']:
char = 6
elif char in ['P','Q','R','S']:
char = 7
elif char in ['T','U','V']:
char = 8
elif char in ['W','X','Y','Z']:
char = 9
return char
main()
方法将其返回。
join()
如果您不能使用def check_number(user_number):
try:
r = ''
for char in user_number:
if char.isalpha():
result = convert_to_num(char)
r += str(result)
else:
r += char
return r
except Exception as err:
print(err)
{{1}}
答案 1 :(得分:0)
此代码:
if char.isalpha():
result = convert_to_num(char)
return result
else:
return char
将立即返回 ,并返回一个数字。您想返回字符串的 all 的所有数字,而不仅仅是返回第一个数字,因此您需要存储输出数字并最终将所有数字(在for循环完成之后)全部返回为单个数字字符串。
初始化一个空列表output = []
并在for循环的每次迭代之后将输出数字附加到它之后,然后返回联接列表(使用"".join()
)是实现此目的的一种好方法。
如果不允许使用"".join()
,也可以只构建一个字符串(output = ""
和output += char
)并直接返回它,但这会比较慢。 / p>