检查列表中的哪些单词可以由一串字母组成

Question

System: Mac Python 2.7

Hi, So I have a list that contains words from the English dictionary I found online. Next, I have a string of lowercase letters . What I want to do is find all the words in the list (English dictionary) that are made of letters in the string and save them to a separate list. Also, I do not want to be able to reuse letters (glue -> glee) but the letters given can be rearranged. An example string could be "hideg" and the result should generate a list containing:

['hide','hid','hie','dig','eh','he','hi','die','ed','id','i']

Here is what I have got so far (Note: myWord is the list (english dictionary) and myLetters is the string):

def validWord(myWord, myLetters): 

    myLetters = "".join(sorted(myLetters))
    matches = []
    for i in myWord:

        if "".join(sorted(i)) in myLetters:

            matches.append(i)

    return matches

Answer 1

The problem in your code is that you are comparing exact match, which in most cases the letters are not fully used, ie. hide != hideg, but of course it can form the word.

One easy way (although not optimized) is to make use of collections.Counter , like this:

In [32]: from collections import Counter

In [33]: words = ['hide','hid','hie','dig','eh','he','hi','die','ed','id','i']

In [34]: letters = 'hide'

In [35]: def valid_word(words, letters):
   ....:     results = []
             # looping through words list and do a comparison
   ....:     for word in words:
                 # build a letter counter for letters
   ....:         letter_counter = Counter(letters)
                 # subtract their letter count, -ve means cannot form the word
   ....:         letter_counter.subtract(Counter(word))
   ....:         if any(c < 0 for c in letter_counter.values()):
   ....:             continue
                 # only append the result if >=0 letters left in counter
   ....:         results.append(word)
   ....:     return results
   ....: 

Usage:

In [36]: valid_word(words, letters)
Out[36]: ['hide', 'hid', 'hie', 'eh', 'he', 'hi', 'die', 'ed', 'id', 'i']

In [37]: valid_word(words, 'hideg')
Out[37]: ['hide', 'hid', 'hie', 'dig', 'eh', 'he', 'hi', 'die', 'ed', 'id', 'i']