生成不同长度的单词,给出n个字符

时间:2018-06-28 23:05:36

标签: python string algorithm data-structures words

我需要生成给定n个字符的Ki长度的所有可能单词,例如:

给定

LNDJOBEAWRL

做 熊

我无法提出len 5的字眼,但这是个主意

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:

{
    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, '}]
}

修改后的代码如下:

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():

2 个答案:

答案 0 :(得分:0)

第一件事是对单词进行标准化,以便彼此相同的两个词的完全相同的处理方式。我们可以通过将其转换为小写并对该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的出现的数字。

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

现在,我们为每个单词提供了标准的表示形式,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,您需要将一个空的trie作为根,并以任何符号作为符号,专门用于保存所有顶级尝试。然后遍历我们之前转换的每个单词,并针对我们产生的第一个符号,检查根特里是否有带有该符号的子代。如果不是,请为其创建一个trie并添加它。如果是这样,请继续执行下一个符号,并检查带有该符号的trie是否在上一个trie中。以这种方式进行操作,直到用完所有符号为止,在这种情况下,当前的trie节点代表了我们转换后的单词的标准化形式。将原始单词存储在此单词中,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单词的符号组成的单词。

答案 1 :(得分:0)

下面的代码使用递归生成器来构建解决方案。要存储目标字母,我们使用collections.Counter,其作用类似于允许重复项的集合。

为简化搜索,我们为所需的每个单词长度创建一个字典,将每个字典存储在名为all_words的字典中,并以单词长度作为关键字。每个子词典都存储包含相同字母的单词列表,并以排序的字母作为关键字,例如'aet': ['ate', 'eat', 'tea']

我使用标准的Unix'/ usr / share / dict / words'字文件。如果您使用其他格式的文件,则可能需要修改将单词放入all_words的代码。

solve函数以最小的字长开始搜索,直到最大字长为止。如果包含最长单词的集合最大,则这可能是最有效的顺序,因为最终搜索是通过执行简单的字典查找来执行的,这非常快。先前的搜索必须测试该长度的子词典中的每个单词,以查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,但需要进行更改

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

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