cs50 可读性 pset6 python 这段代码应该计算单词、句子和字母的数量，但它没有

Question

from cs50 import get_string
letter=0
sentence=0
word=0
text = get_string("Text: ")
n = len(text)
for i in range(n):
    if text[i].isalnum()==True:
        letter=letter+1
for i in range(n):
    if text[i].isspace()==True and text[i+1].isalnum()==True:
        word=word+1
for i in range(n):
    if text[i]=="?" or text[i]=="." or text[i]=="!":
        sentence=sentence+1
grade = round (0.0588 * ((100 * letter) / word) - 0.296 * ((100 * sentence) / word) - 15.8)
if grade<1:
    print("Before Grade 1")
elif grade < 16:
    print(f"Grade {grade}")
else :
    print("Grade 16+");

https://submit.cs50.io/check50/d3897b249b2ca6ea937d023c25c1607af52ea5cd the checks is bad

may be i do something false in it

Answer 1

You have a couple issues here:

The first one is using Text at the beginning (not standard, by the way) vs text . That should help you out quite a bit.

The second is that you aren't actually using the get_string method. Now, it's possible this works for you; I just threw it into a Juypter Notebook because I wanted to work with it like a REPL. But, assuming not, let's briefly step through it.

Conda environment or pip install with cs50 and run that:

Runs fine with no errors. Good. Now the first block:

letter=0
sentence=0
word=0
Text = get_string("Text: ")

That (because I'm using a notebook) evaluates as:

Text: None

Now, maybe there is something specific you are to use in the cs50 library but I used input -- and changed Text to lower case.

But you were on the right path.

Answer 2

There are a couple of problems with the way program counts words. It is doing so by counting spaces (good plan), but

1. How will it count the last word? It won't (because it's not "followed by" a space). You could consider initializing word to 1 (instead of 0).
2. Will it count words in the following passage correctly? Again, no. This if text[i].isspace()==True and text[i+1].isalnum()==True: only counts spaces followed by az, AZ, or 0-9. In this case, it will not count the space after "Alice", so word count is incorrect.

thought Alice "without pictures or conversation?"

A side note: accessing i + 1 in the i loop is generally speaking a very bad idea; it will be outside the range when i reaches the maximum. It hasn't failed in testing because no tested texts end with a space. If you want to see it fail, enter a text that ends with a space.

Answer 3

1) Initialized word to 1; 2) Added the following to assume that a letter is any lower/uppercase character: for i in range(n): if text[i].isalnum() or text[i].isupper() or text[i].islower() == True: letter = letter+1 3) Removed for word count: and text[i+1].isalnum()==True:

Now your code is 10/10!

Answer 4

Try initializing word to 1, removing 'round' before CLI, and adding round to you second to last print statement. Example: {round(grade)}

I had similar code, worked for me.

Answer 5

很棒的工作，我修复了它，只在此处添加了最后一部分：

if text[i]=="?" or text[i]=="." or text[i]=="!" or text[i]==":":

Answer 6

您应该分配word = 1而不是word = 0 （第 4 行）