生成不同长度的单词给出 n 个字符

Generate words of varying length give n number of characters

给定 n 个字符,我需要生成所有可能的 Ki 长度的单词,例如:

给定

LNDJOBEAWRL

做 熊

我想不出 len 5 这个词,但这就是我的想法

n = 11
k1 = 2
k2 = 4
k3 = 5 

所以基本上所有长度为 2 4 和 5 的单词都没有重复使用字符。最好的方法是什么?


我的字典结构如下所示:

{
    3: [{u'eit': u' "eit":0'}], 
    5: [{u'doosw': u' "woods": 4601, '}, {u'acenr': u' "caner": 0, '}, {u'acens': u' "canes": 0, '}, {u'acden': u' "caned": 0, '}, {u'aceln': u' "canel": 0,'}], 
    6: [{u'abeill': u' "alible": 0, '}, {u'cdeeit': u' "deciet":0,'}, {u'demoor': u' "mooder": 0, '}], 
    7: [{u'deiprss': u' "spiders": 0, '}, {u'deiprsy': u' "spidery": 0, '}, {u'cersttu': u' "scutter": 0, '}], 
    8: [{u'chiiilst': u' "chilitis": 0, '}, {u'agilnrtw': u' "trawling": 0, '}, {u'abdeemns': u' "beadsmen": 0, '}], 
    9: [{u'abeiilnns': u' "biennials": 0, '}, {u'bclooortu': u' "oblocutor": 0, '}, {u'aabfiinst': u' "fabianist": 0, '}, {u'acdeiituz': u' "diazeutic": 0, '}, {u'aabfiimns': u' "fabianism": 0, '}, {u'ehnoooppt': u' "optophone": 0, '}], 
    10: [{u'aiilnoprtt': u' "tripolitan": 0, '}, {u'eeilprrsty': u' "sperrylite": 0, '}, {u'gghhiilttt': u' "lighttight": 0, '}, {u'aeegilrruz': u' "regularize": 0, '}, {u'ellnprtuuy': u' "purulently": 0, '}], 
    11: [{u'cdgilnoostu': u' "outscolding": 0, '}], 
    12: [{u'ceeeilnostuy': u' "leucosyenite": 0, '}, {u'aacciloprsst': u' "sarcoplastic": 0, '}], 
    13: [{u'acdeimmoprrsu': u' "cardiospermum": 0, '}, {u'celnnooostuvy': u' "noncovetously": 0, '}], 
    14: [{u'adeejmnnoprrtu': u' "preadjournment": 0, '}]
}

我修改后的代码如下所示:

wlen = self.table[pos]
if pos == 0:
    # See if the letters remaining in the bag are a valid word
    key = ''.join(sorted(bag.elements()))

    for d in wlen:
        if key in d.keys():
            yield solution + [key]
else:
    pos -= 1
    for dic in wlen:
        print(len(dic))
        for key in dic.keys():

首先是对单词进行标准化,这样两个互为变位词的单词将得到完全相同的处理。我们可以通过转换为小写字母并对单词的字母进行排序来做到这一点。下一步是区分给定字母的多次出现。为此,我们将每个字母映射到一个包含该字母的符号,以及一个表示它在字符串中出现的数字。

target = "LNDJOBEAWRL".lower()
symbols = sorted([c + str(target[i+1:].count(c)) for i, c in enumerate(target)])

现在我们有了每个单词的标准表示,我们需要一种快速的方法来检查是否有任何排列匹配它们。为此,我们使用 trie datastructure。这是其中一个的一些入门代码:

class Trie:
    def __init__(self, symbol):
        self.symbol = symbol
        self.words = []
        self.children = dict()

    def add_word(self, word):
        self.words.append(word)

    def add_child(self, symbol, trie):
        self.children[symbol] = trie

现在你需要做一个空的trie作为根,以任何东西作为符号,专门用来存放所有顶级的trie。然后遍历我们之前转换的每个单词,对于我们生成的第一个符号,检查根树是否有带有该符号的子树。如果没有,则为其创建一个 trie 并添加它。如果是,则继续下一个符号,并检查具有该符号的 trie 是否在前一个 trie 中。以这种方式进行,直到用尽所有符号,在这种情况下,当前的 trie 节点代表我们转换的那个词的标准化形式。把原来的单词存入这个trie,然后继续下一个单词。

完成后,您的整个单词列表将包含在此 trie 数据结构中。然后,您可以执行以下操作:

def print_words(symbols, node):
    for word in node.words:
        print(word)
    for sym in node.children:
        if sym in symbols:
            print_words(symbols, node.children[sym])

print_words(symbols, root_trie)

打印所有可以由目标词的符号组成的词。

下面的代码使用递归生成器来构建解决方案。为了存储目标字母,我们使用 collections.Counter,这就像一个允许重复项的集合。

为了简化搜索,我们为每个需要的单词长度创建一个字典,将每个字典存储在一个名为 all_words 的字典中,单词长度作为键。每个子词典存储包含相同字母的单词列表,以排序的字母作为键,例如 'aet': ['ate', 'eat', 'tea'].

我使用标准的 Unix '/usr/share/dict/words' word 文件。如果您使用不同格式的文件,您可能需要修改将单词放入 all_words 的代码。

solve 函数从最小字长开始搜索,一直搜索到最大字长。如果包含最长单词的集合是最大的,那么这可能是最有效的顺序,因为最终搜索是通过简单的字典查找执行的,速度非常快。先前的搜索必须测试该长度的子词典中的每个单词,寻找仍在目标包中的键。

#!/usr/bin/env python3

''' Create anagrams from a string of target letters and a list of word lengths '''

from collections import Counter
from itertools import product

# The Unix word list
fname = '/usr/share/dict/words'

# The target letters to use
target = 'lndjobeawrl'

# Word lengths, in descending order
wordlengths = [5, 4, 2]

# A dict to hold dicts for each word length.
# The inner dicts store lists of words containing the same letters,
# with the sorted letters as the key, eg 'aet': ['ate', 'eat', 'tea']
all_words = {i: {} for i in wordlengths}

# A method that tests if a word only contains letters in target
valid = set(target).issuperset

print('Scanning', fname, 'for valid words...')
count = 0
with open(fname) as f:
    for word in f:
        word = word.rstrip()
        wlen = len(word)
        # Only add words of the correct length, with no punctuation.
        # Using word.islower() eliminates most abbreviations.
        if (wlen in wordlengths and word.islower()
        and word.isalpha() and valid(word)):
            sorted_word = ''.join(sorted(word))
            # Add this word to the list in all_words[wlen],
            # creating the list if it doesn't exist
            all_words[wlen].setdefault(sorted_word, []).append(word)
            count += 1

print(count, 'words found')
for k, v in all_words.items():
    print(k, len(v))
print('\nSolving...')

def solve(pos, bag, solution):
    wlen = wordlengths[pos]
    if pos == 0:
        # See if the letters remaining in the bag are a valid word
        key = ''.join(sorted(bag.elements()))
        if key in all_words[wlen]:
            yield solution + [key]
    else:
        pos -= 1
        for key in all_words[wlen].keys():
            # Test that all letters in key are in the bag
            newbag = bag.copy()
            newbag.subtract(key)
            if all(v >= 0 for v in newbag.values()):
                # Add this key to the current solution and 
                # recurse to find the next key
                yield from solve(pos, newbag, solution + [key])

# Find all lists of keys that produce valid combinations
for solution in solve(len(wordlengths) - 1, Counter(target), []):
    # Convert solutions to tuples of words
    t = [all_words[len(key)][key] for key in solution]
    for s in product(*t):
        print(s)

输出

Scanning /usr/share/dict/words for valid words...
300 words found
5 110
4 112
2 11

Solving...
('ad', 'jell', 'brown')
('do', 'jell', 'brawn')
('ow', 'jell', 'brand')
('re', 'jowl', 'bland')

FWIW,这是

的结果
target = 'nobigword'
wordlengths = [4, 3, 2]

输出

Scanning /usr/share/dict/words for valid words...
83 words found
4 31
3 33
2 7

Solving...
('do', 'big', 'worn')
('do', 'bin', 'grow')
('do', 'nib', 'grow')
('do', 'bow', 'grin')
('do', 'bow', 'ring')
('do', 'gin', 'brow')
('do', 'now', 'brig')
('do', 'own', 'brig')
('do', 'won', 'brig')
('do', 'orb', 'wing')
('do', 'rob', 'wing')
('do', 'rib', 'gown')
('do', 'wig', 'born')
('go', 'bid', 'worn')
('go', 'bin', 'word')
('go', 'nib', 'word')
('go', 'bow', 'rind')
('go', 'din', 'brow')
('go', 'now', 'bird')
('go', 'own', 'bird')
('go', 'won', 'bird')
('go', 'orb', 'wind')
('go', 'rob', 'wind')
('go', 'rib', 'down')
('go', 'row', 'bind')
('id', 'bog', 'worn')
('id', 'gob', 'worn')
('id', 'orb', 'gown')
('id', 'rob', 'gown')
('id', 'row', 'bong')
('in', 'bog', 'word')
('in', 'gob', 'word')
('in', 'dog', 'brow')
('in', 'god', 'brow')
('no', 'bid', 'grow')
('on', 'bid', 'grow')
('no', 'big', 'word')
('on', 'big', 'word')
('no', 'bow', 'gird')
('no', 'bow', 'grid')
('on', 'bow', 'gird')
('on', 'bow', 'grid')
('no', 'dig', 'brow')
('on', 'dig', 'brow')
('or', 'bid', 'gown')
('or', 'big', 'down')
('or', 'bog', 'wind')
('or', 'gob', 'wind')
('or', 'bow', 'ding')
('or', 'wig', 'bond')
('ow', 'bog', 'rind')
('ow', 'gob', 'rind')
('ow', 'dig', 'born')
('ow', 'don', 'brig')
('ow', 'nod', 'brig')
('ow', 'orb', 'ding')
('ow', 'rob', 'ding')
('ow', 'rid', 'bong')
('ow', 'rig', 'bond')

此代码是为 Python 3 编写的。您可以在 Python 2.7 上使用它,但您需要更改

yield from solve(pos, newbag, solution + [key])

for result in solve(pos, newbag, solution + [key]):
    yield result