我有一个令牌列表,例如:
hel
lo
bye
我希望生成这些字符串的所有可能组合,例如:
hello
lohel
helbye
byehel
lobye
byelo
语言不重要,有什么建议吗?
我找到Generating permutations using bash,但这会在一行上进行排列。
答案 0 :(得分:18)
您的示例可以用Python编写
from itertools import combinations
print list(combinations(["hel", "lo", "bye"], 2))
将输出再次组合到字符串:
print ["".join(a) for a in combinations(["hel", "lo", "bye"], 2)]
如果您对此功能的实际实施感兴趣,请查看documentation。
答案 1 :(得分:6)
itertools.permutations
可以为您做到这一点。
>>> l = ['hel', 'lo', 'bye']
>>> list(itertools.permutations(l, 2))
[('hel', 'lo'), ('hel', 'bye'), ('lo', 'hel'), ('lo', 'bye'), ('bye', 'hel'), ('bye', 'lo')]
或者如果您想要组合,可以使用itertools.combinations
。
>>> l = ['hel', 'lo', 'bye']
>>> list(itertools.combinations(l, 2))
[('hel', 'lo'), ('hel', 'bye'), ('lo', 'bye')]
答案 2 :(得分:3)
鉴于其他语言可以接受:
#!/usr/bin/perl
use strict; use warnings;
use Algorithm::Combinatorics qw(permutations);
my $data = [ qw( hel lo bye ) ];
my $it = permutations($data);
while ( my $p = $it->next ) {
print @$p, "\n";
}
hellobye helbyelo lohelbye lobyehel byehello byelohel
答案 3 :(得分:2)
a = ['hel', 'lo', 'bye']
print '\n'.join(''.join(x) for x in itertools.permutations(a, 2))
答案 4 :(得分:1)
使用itertools轻松实现python。
以下是令牌排列示例:
import itertools
tokens = ["hel", "lo", "bye"]
for i in range(1, len(tokens) + 1):
for p in itertools.permutations(tokens, i):
print "".join(p)
或者,这会将每个字符视为一个标记:
import itertools
tokens = ["hel", "lo", "bye"]
chars = "".join(tokens)
for i in range(1, len(chars) + 1):
for p in itertools.permutations(chars, i):
print "".join(p)
答案 5 :(得分:1)
Python也有permutations。 :)
答案 6 :(得分:1)
看起来你想要permutations
:
from itertools import permutations
# easy way to make a list for words
words = 'hel lo bye'.split()
# fetch two-word permutations, joined into a string
for word in [''.join(s) for s in permutations(words,2)]:
print word
hello
helbye
lohel
lobye
byehel
byelo
答案 7 :(得分:0)
更新:我看到我不够明确。
Haskell有permutations函数可以提供帮助:
import Data.List
permutations ["hel","lo","bye"] ==
[["hel","lo","bye"],["lo","hel","bye"],["bye","lo","hel"],
["lo","bye","hel"],["bye","hel","lo"],["hel","bye","lo"]]
如果您想要连接每个排列,请使用
map concat (permutations ["hel","lo","bye"]) ==
["hellobye","lohelbye","byelohel","lobyehel","byehello","helbyelo"]
如果你真的想要两个子串的组合(比如你的示例输出)而不是所有排列的子串,就像@Sven注意到的那样,使用Math.Combinatorics.Graph模块和:
map concat (combinationsOf 2 ["hel","lo","bye"])
这在某些方面与您的示例数据匹配,但与其他方面不匹配。我可以继续推测你想要标题所说的“所有可能的字符串”,或者双标记子集的所有排列,或者你有什么,但是因为你已经接受了答案,所以推测它是毫无意义的。 / p>