Merge of lazy streams (using generators) in Python

Question

I\'m playing with functional capacities of Python 3 and I tried to implement classical algorithm for calculating Hamming numbers. That\'s the numbers which have as prime fac

Answer 1

I will propose this different approach - using Python heapq (min-heapq) with generator (lazy evaluation) (if you don't insist to keep the merge() function)

from heapq import heappush, heappop

def hamming_numbers(n):
    ans = [1]

    last = 0
    count = 0

    while count < n:
        x = heappop(ans)

        if x > last:
            yield x

            last = x
            count += 1

            heappush(ans, 2* x)
            heappush(ans, 3* x)
            heappush(ans, 5* x)


    >>> n  = 20
    >>> print(list(hamming_numbers(20)))
       [1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 16, 18, 20, 24, 25, 27, 30, 32, 36]