Good algorithm for combining items from N lists into one with balanced distribution?

Question

Let\'s say I have the three following lists

A1
A2
A3

B1
B2

C1
C2
C3
C4
C5

I\'d like to combine them into a si

Answer 1

A quick suggestion, in python-ish pseudocode:

merge = list()
lists = list(list_a, list_b, list_c)
lists.sort_by(length, descending)

while lists is not empty:
    l = lists.remove_first()
    merge.append(l.remove_first())
    if l is not empty:
        next = lists.remove_first()
        lists.append(l)
        lists.sort_by(length, descending)
        lists.prepend(next)

This should distribute elements from shorter lists more evenly than the other suggestions here.