Python分区功能

Question

I have the following code which I adapted from code that was previously posted on this site. It is a variation on the a partition function that outputs all possible combination of numbers that add up to a specified sum, but it limits the numbers that can be used for the sum to a limited input list.

def part(nr, Nums):
    nrs = sorted(Nums, reverse=True)

    def inner(n, i):
        if n == 0:
            yield []
        for k in range(i, len(nrs)):
            if nrs[k] <= n:
                for rest in inner(n - nrs[k], k):
                    yield [nrs[k]] + rest

    return list(inner(nr, 0))


#List of numbers to form the sums.
Nums = [5,6 ,7 ,8, 9, 10]

#the total that the numbers add up to.
total = 32

tr = part(total, Nums)

print(f"{len(tr)}  Combination of {Nums} in {total} are:")
print(tr)

results:

24 Combination of [5, 6, 7, 8, 9, 10] in 32 are:

[[10, 10, 7, 5], [10, 10, 6, 6], [10, 9, 8, 5], [10, 9, 7, 6], [10, 8, 8, 6], [10, 8, 7, 7], [10, 7, 5, 5, 5], [10, 6, 6, 5, 5], [9, 9, 9, 5], [9, 9, 8, 6], [9, 9, 7, 7], [9, 8, 8, 7], [9, 8, 5, 5, 5], [9, 7, 6, 5, 5], [9, 6, 6, 6, 5], [8, 8, 8, 8], [8, 8, 6, 5, 5], [8, 7, 7, 5, 5], [8, 7, 6, 6, 5], [8, 6, 6, 6, 6], [7, 7, 7, 6, 5], [7, 7, 6, 6, 6], [7, 5, 5, 5, 5, 5], [6, 6, 5, 5, 5, 5]]

Process finished with exit code 0

Everything is working as expected but I want to change it so each number can only be used once or none at all in each possible combination.

So for example: "[10, 8, 7, 7], [10, 7, 5, 5, 5]," These combination sums would not be outputted since they contain repeating sevens and fives respectively.

I'm trying to keep the generator functions because I was told that they have better performance than lists and I might use the same function for larger lists and sums in the future. But I am not sure how to check the generator for duplicate numbers to eliminate the sub-lists that contain repeating numbers.

Thanks.

Answer 1

您可以将第7行更改为： for k in range(i + 1, len(nrs)):