如何从对列表中检索对组合，而没有任何单个元素在一对以上？

Question

If I have a list of pairs, such as

[(egg,man),(egg,dog),(cat,cactus),(cactus,elephant),(giraffe,chocolate),(tea,boat),(sky,lizard),(sky,tree),(helicopter,lizard)]

How would I retrieve the most amount of pairs possible without any single element being in more than one pair? What I would want to retrieve is something like this:

(egg,man),(cat,cactus),(giraffe,chocolate),(tea,boat),(sky,lizard)

So that every pair only contains unique elements, and I get the most possible.

Answer 1

This worked for me:

words = [('egg','man'),('egg','dog'),('cat','cactus'),('cactus','elephant'),('giraffe','chocolate'),('tea','boat'),('sky','lizard'),('sky','tree'),('helicopter','lizard')]

new_words = []

count = 0

for i in range(len(words)):
    for k in range(len(words[i])):
        if words[i][k] not in [item for t in new_words for item in t]:
            count += 1
        if count == 2:
            new_words.append(words[i])
    count = 0

The list new_words is the list that you want.