合并具有共同元素的列表
- 2025-02-05 13:23:00
- admin 原创
- 62
问题描述:
我的输入是一串列表。其中一些列表有共同的元素,例如:
L = [['a','b','c'],['b','d','e'],['k'],['o','p'],['e','f'],['p','a'],['d','g']]
我需要合并所有共享一个公共元素的列表,并重复此过程,直到不再有具有相同项目的列表。我考虑过使用布尔运算和 while 循环,但想不出好的解决方案。
最终结果应该是:
L = [['a','b','c','d','e','f','g','o','p'],['k']]
解决方案 1:
您可以将列表视为图形的符号,即['a','b','c']
具有 3 个相互连接的节点的图形。您要解决的问题是在此图形中找到连通分量。
您可以为此使用NetworkX,它的优点是几乎可以保证正确性:
l = [['a','b','c'],['b','d','e'],['k'],['o','p'],['e','f'],['p','a'],['d','g']]
import networkx
from networkx.algorithms.components.connected import connected_components
def to_graph(l):
G = networkx.Graph()
for part in l:
# each sublist is a bunch of nodes
G.add_nodes_from(part)
# it also imlies a number of edges:
G.add_edges_from(to_edges(part))
return G
def to_edges(l):
"""
treat `l` as a Graph and returns it's edges
to_edges(['a','b','c','d']) -> [(a,b), (b,c),(c,d)]
"""
it = iter(l)
last = next(it)
for current in it:
yield last, current
last = current
G = to_graph(l)
print connected_components(G)
# prints [['a', 'c', 'b', 'e', 'd', 'g', 'f', 'o', 'p'], ['k']]
为了自己有效地解决这个问题,你必须将列表转换成图形形式,因此你最好从一开始就使用 networkX。
解决方案 2:
算法:
从列表中取出第一组 A
对于列表中的每个其他集合 B,如果 B 具有与 A 的共同元素,则将 B 合并到 A;从列表中删除 B
重复2.直到不再与A重叠
将 A 放入输出
重复 1. 其余列表
因此,您可能希望使用集合而不是列表。以下程序应该可以做到这一点。
l = [['a', 'b', 'c'], ['b', 'd', 'e'], ['k'], ['o', 'p'], ['e', 'f'], ['p', 'a'], ['d', 'g']]
out = []
while len(l)>0:
first, *rest = l
first = set(first)
lf = -1
while len(first)>lf:
lf = len(first)
rest2 = []
for r in rest:
if len(first.intersection(set(r)))>0:
first |= set(r)
else:
rest2.append(r)
rest = rest2
out.append(first)
l = rest
print(out)
解决方案 3:
我需要对相当大的列表执行 OP 描述的聚类技术数百万次,因此想确定上面建议的哪种方法最准确、性能最好。
我对上述每种方法进行了 10 次试验,输入列表大小从 2^1 到 2^10,每种方法使用相同的输入列表,并以毫秒为单位测量了上述每种算法的平均运行时间。结果如下:
这些结果帮助我看到,在始终返回正确结果的方法中,@jochen 的方法速度最快。在那些不能始终返回正确结果的方法中,mak 的解决方案通常不包括所有输入元素(即缺少列表成员列表),而 braaksma、cmangla 和 asterisk 的解决方案不能保证最大程度地合并。
有趣的是,按照正确的排名顺序,迄今为止,速度最快、正确的两种算法获得的赞成票数位居前两位。
以下是用于运行测试的代码:
from networkx.algorithms.components.connected import connected_components
from itertools import chain
from random import randint, random
from collections import defaultdict, deque
from copy import deepcopy
from multiprocessing import Pool
import networkx
import datetime
import os
##
# @mimomu
##
def mimomu(l):
l = deepcopy(l)
s = set(chain.from_iterable(l))
for i in s:
components = [x for x in l if i in x]
for j in components:
l.remove(j)
l += [list(set(chain.from_iterable(components)))]
return l
##
# @Howard
##
def howard(l):
out = []
while len(l)>0:
first, *rest = l
first = set(first)
lf = -1
while len(first)>lf:
lf = len(first)
rest2 = []
for r in rest:
if len(first.intersection(set(r)))>0:
first |= set(r)
else:
rest2.append(r)
rest = rest2
out.append(first)
l = rest
return out
##
# Nx @Jochen Ritzel
##
def jochen(l):
l = deepcopy(l)
def to_graph(l):
G = networkx.Graph()
for part in l:
# each sublist is a bunch of nodes
G.add_nodes_from(part)
# it also imlies a number of edges:
G.add_edges_from(to_edges(part))
return G
def to_edges(l):
"""
treat `l` as a Graph and returns it's edges
to_edges(['a','b','c','d']) -> [(a,b), (b,c),(c,d)]
"""
it = iter(l)
last = next(it)
for current in it:
yield last, current
last = current
G = to_graph(l)
return list(connected_components(G))
##
# Merge all @MAK
##
def mak(l):
l = deepcopy(l)
taken=[False]*len(l)
l=map(set,l)
def dfs(node,index):
taken[index]=True
ret=node
for i,item in enumerate(l):
if not taken[i] and not ret.isdisjoint(item):
ret.update(dfs(item,i))
return ret
def merge_all():
ret=[]
for i,node in enumerate(l):
if not taken[i]:
ret.append(list(dfs(node,i)))
return ret
result = list(merge_all())
return result
##
# @cmangla
##
def cmangla(l):
l = deepcopy(l)
len_l = len(l)
i = 0
while i < (len_l - 1):
for j in range(i + 1, len_l):
# i,j iterate over all pairs of l's elements including new
# elements from merged pairs. We use len_l because len(l)
# may change as we iterate
i_set = set(l[i])
j_set = set(l[j])
if len(i_set.intersection(j_set)) > 0:
# Remove these two from list
l.pop(j)
l.pop(i)
# Merge them and append to the orig. list
ij_union = list(i_set.union(j_set))
l.append(ij_union)
# len(l) has changed
len_l -= 1
# adjust 'i' because elements shifted
i -= 1
# abort inner loop, continue with next l[i]
break
i += 1
return l
##
# @pillmuncher
##
def pillmuncher(l):
l = deepcopy(l)
def connected_components(lists):
neighbors = defaultdict(set)
seen = set()
for each in lists:
for item in each:
neighbors[item].update(each)
def component(node, neighbors=neighbors, seen=seen, see=seen.add):
nodes = set([node])
next_node = nodes.pop
while nodes:
node = next_node()
see(node)
nodes |= neighbors[node] - seen
yield node
for node in neighbors:
if node not in seen:
yield sorted(component(node))
return list(connected_components(l))
##
# @NicholasBraaksma
##
def braaksma(l):
l = deepcopy(l)
lists = sorted([sorted(x) for x in l]) #Sorts lists in place so you dont miss things. Trust me, needs to be done.
resultslist = [] #Create the empty result list.
if len(lists) >= 1: # If your list is empty then you dont need to do anything.
resultlist = [lists[0]] #Add the first item to your resultset
if len(lists) > 1: #If there is only one list in your list then you dont need to do anything.
for l in lists[1:]: #Loop through lists starting at list 1
listset = set(l) #Turn you list into a set
merged = False #Trigger
for index in range(len(resultlist)): #Use indexes of the list for speed.
rset = set(resultlist[index]) #Get list from you resultset as a set
if len(listset & rset) != 0: #If listset and rset have a common value then the len will be greater than 1
resultlist[index] = list(listset | rset) #Update the resultlist with the updated union of listset and rset
merged = True #Turn trigger to True
break #Because you found a match there is no need to continue the for loop.
if not merged: #If there was no match then add the list to the resultset, so it doesnt get left out.
resultlist.append(l)
return resultlist
##
# @Rumple Stiltskin
##
def stiltskin(l):
l = deepcopy(l)
hashdict = defaultdict(int)
def hashit(x, y):
for i in y: x[i] += 1
return x
def merge(x, y):
sums = sum([hashdict[i] for i in y])
if sums > len(y):
x[0] = x[0].union(y)
else:
x[1] = x[1].union(y)
return x
hashdict = reduce(hashit, l, hashdict)
sets = reduce(merge, l, [set(),set()])
return list(sets)
##
# @Asterisk
##
def asterisk(l):
l = deepcopy(l)
results = {}
for sm in ['min', 'max']:
sort_method = min if sm == 'min' else max
l = sorted(l, key=lambda x:sort_method(x))
queue = deque(l)
grouped = []
while len(queue) >= 2:
l1 = queue.popleft()
l2 = queue.popleft()
s1 = set(l1)
s2 = set(l2)
if s1 & s2:
queue.appendleft(s1 | s2)
else:
grouped.append(s1)
queue.appendleft(s2)
if queue:
grouped.append(queue.pop())
results[sm] = grouped
if len(results['min']) < len(results['max']):
return results['min']
return results['max']
##
# Validate no more clusters can be merged
##
def validate(output, L):
# validate all sublists are maximally merged
d = defaultdict(list)
for idx, i in enumerate(output):
for j in i:
d[j].append(i)
if any([len(i) > 1 for i in d.values()]):
return 'not maximally merged'
# validate all items in L are accounted for
all_items = set(chain.from_iterable(L))
accounted_items = set(chain.from_iterable(output))
if all_items != accounted_items:
return 'missing items'
# validate results are good
return 'true'
##
# Timers
##
def time(func, L):
start = datetime.datetime.now()
result = func(L)
delta = datetime.datetime.now() - start
return result, delta
##
# Function runner
##
def run_func(args):
func, L, input_size = args
results, elapsed = time(func, L)
validation_result = validate(results, L)
return func.__name__, input_size, elapsed, validation_result
##
# Main
##
all_results = defaultdict(lambda: defaultdict(list))
funcs = [mimomu, howard, jochen, mak, cmangla, braaksma, asterisk]
args = []
for trial in range(10):
for s in range(10):
input_size = 2**s
# get some random inputs to use for all trials at this size
L = []
for i in range(input_size):
sublist = []
for j in range(randint(5, 10)):
sublist.append(randint(0, 2**24))
L.append(sublist)
for i in funcs:
args.append([i, L, input_size])
pool = Pool()
for result in pool.imap(run_func, args):
func_name, input_size, elapsed, validation_result = result
all_results[func_name][input_size].append({
'time': elapsed,
'validation': validation_result,
})
# show the running time for the function at this input size
print(input_size, func_name, elapsed, validation_result)
pool.close()
pool.join()
# write the average of time trials at each size for each function
with open('times.tsv', 'w') as out:
for func in all_results:
validations = [i['validation'] for j in all_results[func] for i in all_results[func][j]]
linetype = 'incorrect results' if any([i != 'true' for i in validations]) else 'correct results'
for input_size in all_results[func]:
all_times = [i['time'].microseconds for i in all_results[func][input_size]]
avg_time = sum(all_times) / len(all_times)
out.write(func + ' ' + str(input_size) + ' ' + \n str(avg_time) + ' ' + linetype + '
')
对于绘图:
library(ggplot2)
df <- read.table('times.tsv', sep=' ')
p <- ggplot(df, aes(x=V2, y=V3, color=as.factor(V1))) +
geom_line() +
xlab('number of input lists') +
ylab('runtime (ms)') +
labs(color='') +
scale_x_continuous(trans='log10') +
facet_wrap(~V4, ncol=1)
ggsave('runtimes.png')
解决方案 4:
我在尝试合并具有共同值的列表时遇到了同样的问题。此示例可能就是您要找的。它只循环一次列表并更新结果集。
lists = [['a','b','c'],['b','d','e'],['k'],['o','p'],['e','f'],['p','a'],['d','g']]
lists = sorted([sorted(x) for x in lists]) #Sorts lists in place so you dont miss things. Trust me, needs to be done.
resultslist = [] #Create the empty result list.
if len(lists) >= 1: # If your list is empty then you dont need to do anything.
resultlist = [lists[0]] #Add the first item to your resultset
if len(lists) > 1: #If there is only one list in your list then you dont need to do anything.
for l in lists[1:]: #Loop through lists starting at list 1
listset = set(l) #Turn you list into a set
merged = False #Trigger
for index in range(len(resultlist)): #Use indexes of the list for speed.
rset = set(resultlist[index]) #Get list from you resultset as a set
if len(listset & rset) != 0: #If listset and rset have a common value then the len will be greater than 1
resultlist[index] = list(listset | rset) #Update the resultlist with the updated union of listset and rset
merged = True #Turn trigger to True
break #Because you found a match there is no need to continue the for loop.
if not merged: #If there was no match then add the list to the resultset, so it doesnt get left out.
resultlist.append(l)
print resultlist
resultset = [['a', 'b', 'c', 'd', 'e', 'g', 'f', 'o', 'p'], ['k']]
解决方案 5:
我发现 itertools 是合并列表的快速选项,它为我解决了这个问题:
import itertools
LL = set(itertools.chain.from_iterable(L))
# LL is {'a', 'b', 'c', 'd', 'e', 'f', 'g', 'k', 'o', 'p'}
for each in LL:
components = [x for x in L if each in x]
for i in components:
L.remove(i)
L += [list(set(itertools.chain.from_iterable(components)))]
# then L = [['k'], ['a', 'c', 'b', 'e', 'd', 'g', 'f', 'o', 'p']]
对于大型集合,按频率从最常见元素到最不常见元素对 LL 进行排序可以加快速度
解决方案 6:
我认为这可以通过将问题建模为图形来解决。每个子列表都是一个节点,并且只有当两个子列表具有某些共同元素时,它们才会与另一个节点共享一条边。因此,合并的子列表基本上是图中的连接组件。合并所有这些只需找到所有连接组件并列出它们即可。
这可以通过对图进行简单的遍历来完成。BFS和 DFS都可以使用,但我在这里使用 DFS,因为它对我来说更短一些。
l = [['a','b','c'],['b','d','e'],['k'],['o','p'],['e','f'],['p','a'],['d','g']]
taken=[False]*len(l)
l=[set(elem) for elem in l]
def dfs(node,index):
taken[index]=True
ret=node
for i,item in enumerate(l):
if not taken[i] and not ret.isdisjoint(item):
ret.update(dfs(item,i))
return ret
def merge_all():
ret=[]
for i,node in enumerate(l):
if not taken[i]:
ret.append(list(dfs(node,i)))
return ret
print(merge_all())
解决方案 7:
正如Jochen Ritzel 指出的那样,您正在寻找图中的连接组件。以下是在不使用图库的情况下实现它的方法:
from collections import defaultdict
def connected_components(lists):
neighbors = defaultdict(set)
seen = set()
for each in lists:
for item in each:
neighbors[item].update(each)
def component(node, neighbors=neighbors, seen=seen, see=seen.add):
nodes = set([node])
next_node = nodes.pop
while nodes:
node = next_node()
see(node)
nodes |= neighbors[node] - seen
yield node
for node in neighbors:
if node not in seen:
yield sorted(component(node))
L = [['a','b','c'],['b','d','e'],['k'],['o','p'],['e','f'],['p','a'],['d','g']]
print list(connected_components(L))
解决方案 8:
您可以使用 networkx 库,因为这是一个图论和连通分量问题:
import networkx as nx
L = [['a','b','c'],['b','d','e'],['k'],['o','p'],['e','f'],['p','a'],['d','g']]
G = nx.Graph()
#Add nodes to Graph
G.add_nodes_from(sum(L, []))
#Create edges from list of nodes
q = [[(s[i],s[i+1]) for i in range(len(s)-1)] for s in L]
for i in q:
#Add edges to Graph
G.add_edges_from(i)
#Find all connnected components in graph and list nodes for each component
[list(i) for i in nx.connected_components(G)]
输出:
[['p', 'c', 'f', 'g', 'o', 'a', 'd', 'b', 'e'], ['k']]
解决方案 9:
我怀念非 quirurgic 版本。我于 2018 年(7 年后)发布了它
一种简单且稳定的方法:
1)进行笛卡尔积(交叉连接),合并两个有共同点的元素
2)删除重复项
#your list
l=[['a','b','c'],['b','d','e'],['k'],['o','p'],['e','f'],['p','a'],['d','g']]
#import itertools
from itertools import product, groupby
#inner lists to sets (to list of sets)
l=[set(x) for x in l]
#cartesian product merging elements if some element in common
for a,b in product(l,l):
if a.intersection( b ):
a.update(b)
b.update(a)
#back to list of lists
l = sorted( [sorted(list(x)) for x in l])
#remove dups
list(l for l,_ in groupby(l))
#result
[['a', 'b', 'c', 'd', 'e', 'f', 'g', 'o', 'p'], ['k']]
解决方案 10:
我的尝试。看起来功能齐全。
#!/usr/bin/python
from collections import defaultdict
l = [['a','b','c'],['b','d','e'],['k'],['o','p'],['e','f'],['p','a'],['d','g']]
hashdict = defaultdict(int)
def hashit(x, y):
for i in y: x[i] += 1
return x
def merge(x, y):
sums = sum([hashdict[i] for i in y])
if sums > len(y):
x[0] = x[0].union(y)
else:
x[1] = x[1].union(y)
return x
hashdict = reduce(hashit, l, hashdict)
sets = reduce(merge, l, [set(),set()])
print [list(sets[0]), list(sets[1])]
解决方案 11:
这是一个相当快的解决方案,没有任何依赖关系。它的工作原理如下:
为每个子项分配一个唯一的参考编号(在本例中为子列表的初始索引)
为每个子列表以及每个子列表中的每个项目创建一个参考元素的字典。
重复以下步骤,直到不再产生变化:
遍历每个子列表中的每个项目。如果该项目的当前引用编号与其子列表的引用编号不同,则该元素必须是两个列表的一部分。合并两个列表(从引用中删除当前子列表),并将当前子列表中所有项目的引用编号设置为新子列表的引用编号。
如果此过程不会引起任何变化,这是因为所有元素都属于同一个列表。由于工作集在每次迭代中都会减小,因此算法必然会终止。
def merge_overlapping_sublists(lst):
output, refs = {}, {}
for index, sublist in enumerate(lst):
output[index] = set(sublist)
for elem in sublist:
refs[elem] = index
changes = True
while changes:
changes = False
for ref_num, sublist in list(output.items()):
for elem in sublist:
current_ref_num = refs[elem]
if current_ref_num != ref_num:
changes = True
output[current_ref_num] |= sublist
for elem2 in sublist:
refs[elem2] = current_ref_num
output.pop(ref_num)
break
return list(output.values())
以下是针对该代码的一组测试:
def compare(a, b):
a = list(b)
try:
for elem in a:
b.remove(elem)
except ValueError:
return False
return not b
import random
lst = [["a", "b"], ["b", "c"], ["c", "d"], ["d", "e"]]
random.shuffle(lst)
assert compare(merge_overlapping_sublists(lst), [{"a", "b", "c", "d", "e"}])
lst = [["a", "b"], ["b", "c"], ["f", "d"], ["d", "e"]]
random.shuffle(lst)
assert compare(merge_overlapping_sublists(lst), [{"a", "b", "c",}, {"d", "e", "f"}])
lst = [["a", "b"], ["k", "c"], ["f", "g"], ["d", "e"]]
random.shuffle(lst)
assert compare(merge_overlapping_sublists(lst), [{"a", "b"}, {"k", "c"}, {"f", "g"}, {"d", "e"}])
lst = [["a", "b", "c"], ["b", "d", "e"], ["k"], ["o", "p"], ["e", "f"], ["p", "a"], ["d", "g"]]
random.shuffle(lst)
assert compare(merge_overlapping_sublists(lst), [{"k"}, {"a", "c", "b", "e", "d", "g", "f", "o", "p"}])
lst = [["a", "b"], ["b", "c"], ["a"], ["a"], ["b"]]
random.shuffle(lst)
assert compare(merge_overlapping_sublists(lst), [{"a", "b", "c"}])
请注意,返回值是一个集合列表。
解决方案 12:
在不知道您想要什么的情况下,我决定猜测您的意思是:我只想找到每个元素一次。
#!/usr/bin/python
def clink(l, acc):
for sub in l:
if sub.__class__ == list:
clink(sub, acc)
else:
acc[sub]=1
def clunk(l):
acc = {}
clink(l, acc)
print acc.keys()
l = [['a', 'b', 'c'], ['b', 'd', 'e'], ['k'], ['o', 'p'], ['e', 'f'], ['p', 'a'], ['d', 'g']]
clunk(l)
输出如下:
['a', 'c', 'b', 'e', 'd', 'g', 'f', 'k', 'o', 'p']
解决方案 13:
这也许是一个更简单/更快的算法,而且似乎效果很好 -
l = [['a', 'b', 'c'], ['b', 'd', 'e'], ['k'], ['o', 'p'], ['e', 'f'], ['p', 'a'], ['d', 'g']]
len_l = len(l)
i = 0
while i < (len_l - 1):
for j in range(i + 1, len_l):
# i,j iterate over all pairs of l's elements including new
# elements from merged pairs. We use len_l because len(l)
# may change as we iterate
i_set = set(l[i])
j_set = set(l[j])
if len(i_set.intersection(j_set)) > 0:
# Remove these two from list
l.pop(j)
l.pop(i)
# Merge them and append to the orig. list
ij_union = list(i_set.union(j_set))
l.append(ij_union)
# len(l) has changed
len_l -= 1
# adjust 'i' because elements shifted
i -= 1
# abort inner loop, continue with next l[i]
break
i += 1
print l
# prints [['k'], ['a', 'c', 'b', 'e', 'd', 'g', 'f', 'o', 'p']]
解决方案 14:
简单来说,您可以使用快速查找。
关键是使用两个临时列表。第一个列表称为elements,它存储所有组中存在的所有元素。第二个列表称为labels。我的灵感来自 sklearn 的 kmeans 算法。'labels' 存储元素的标签或质心。在这里我简单地让簇中的第一个元素成为质心。最初,值从 0 到 length-1,按升序排列。
对于每个组,我都会在“元素”中获取它们的“索引”。然后,我根据索引获取组的标签。然后,我计算标签的最小值,这将是它们的新标签。我用新标签替换组标签中所有带标签的元素。
或者说,对于每次迭代,我都会尝试合并两个或多个现有组。如果组的标签为 0 和 2,我会找出新标签 0,即两者中的最小值。然后我会用 0 替换它们。
def cluser_combine(groups):
n_groups=len(groups)
#first, we put all elements appeared in 'gruops' into 'elements'.
elements=list(set.union(*[set(g) for g in groups]))
#and sort elements.
elements.sort()
n_elements=len(elements)
#I create a list called clusters, this is the key of this algorithm.
#I was inspired by sklearn kmeans implementation.
#they have an attribute called labels_
#the url is here:
#https://scikit-learn.org/stable/modules/generated/sklearn.cluster.KMeans.html
#i called this algorithm cluster combine, because of this inspiration.
labels=list(range(n_elements))
#for each group, I get their 'indices' in 'elements'
#I then get the labels for indices.
#and i calculate the min of the labels, that will be the new label for them.
#I replace all elements with labels in labels_for_group with the new label.
#or to say, for each iteration,
#i try to combine two or more existing groups.
#if the group has labels of 0 and 2
#i find out the new label 0, that is the min of the two.
#i than replace them with 0.
for i in range(n_groups):
#if there is only zero/one element in the group, skip
if len(groups[i])<=1:
continue
indices=list(map(elements.index, groups[i]))
labels_for_group=list(set([labels[i] for i in indices]))
#if their is only one label, all the elements in group are already have the same label, skip.
if len(labels_for_group)==1:
continue
labels_for_group.sort()
label=labels_for_group[0]
#combine
for k in range(n_elements):
if labels[k] in labels_for_group[1:]:
labels[k]=label
new_groups=[]
for label in set(labels):
new_group = [elements[i] for i, v in enumerate(labels) if v == label]
new_groups.append(new_group)
return new_groups
我打印出了你的问题的详细结果:
cluser_combine([['a','b','c'],['b','d','e'],['k'],['o','p'],['e','f'],['p','a'],['d','g']])
元素:
['a', 'b', 'c', 'd', 'e', 'f', 'g', 'k', 'o', 'p']
标签:
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
--------------------组 0-------------------------
组为:
['a', 'b', 'c']
元素中组的索引
[0, 1, 2]
组合前的标签
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
组合...
组合后的标签
[0, 0, 0, 3, 4, 5, 6, 7, 8, 9]
--------------------组 1-------------------------
组为:
['b', 'd', 'e']
元素中组的索引
[1, 3, 4]组合
前的标签组合
[0, 0, 0, 3, 4, 5, 6, 7, 8, 9]
组合...
组合后的标签
[0, 0, 0, 0, 0, 5, 6, 7, 8, 9]
--------------------组 2-------------------------
组为:
['k']
--------------------组 3-------------------------
组为:
['o', 'p']
元素中组的索引
[8, 9]
组合前的标签
[0, 0, 0, 0, 5, 6, 7, 8, 9]
组合...
组合后的标签
[0, 0, 0, 0, 0, 5, 6, 7, 8, 8]
--------------------组 4-------------------------
组为:
['e', 'f']
元素中组的索引
[4, 5]
组合前的标签
[0, 0, 0, 0, 0, 5, 6, 7, 8, 8]
组合...
组合后的标签
[0, 0, 0, 0, 0, 6, 7, 8, 8]
--------------------组 5-------------------------
组为:
['p', 'a']
元素中组的索引
[9, 0]
组合前的标签
[0, 0, 0, 0, 0, 6, 7, 8, 8]
组合...
组合后的标签
[0, 0, 0, 0, 0, 6, 7, 0, 0]
--------------------组 6-------------------------
组为:
['d', 'g']
元素中组的索引
[3, 6]
组合前的标签
[0, 0, 0, 0, 0, 6, 7, 0, 0]
组合...
组合后的标签
[0, 0, 0, 0, 0, 0, 0, 7, 0, 0]
([0, 0, 0, 0, 0, 0, 0, 7, 0, 0],
[['a', 'b', 'c', 'd', 'e', 'f', 'g', 'o', 'p'], ['k']])
详情请参考我的github jupyter notebook
解决方案 15:
这是我的答案。
orig = [['a','b','c'],['b','d','e'],['k'],['o','p'],['e','f'],['p','a'],['d','g'], ['k'],['k'],['k']]
def merge_lists(orig):
def step(orig):
mid = []
mid.append(orig[0])
for i in range(len(mid)):
for j in range(1,len(orig)):
for k in orig[j]:
if k in mid[i]:
mid[i].extend(orig[j])
break
elif k == orig[j][-1] and orig[j] not in mid:
mid.append(orig[j])
mid = [sorted(list(set(x))) for x in mid]
return mid
result = step(orig)
while result != step(result):
result = step(result)
return result
merge_lists(orig)
[['a', 'b', 'c', 'd', 'e', 'f', 'g', 'o', 'p'], ['k']]