how do i do round-robin in python 3

Question

i have to do a rotation of a list. I get a sorted list and i have to get minimum of pairs and maximum of tree numbers in a permutation of this sorted list as an answear. It has to have different numbers sorted from lowest to highest. For example:

MyList=[1, 1, 1, 2, 2, 2, 3, 3, 3, 3]

and the output must be:

1 2 3
1 2 3
1 3
2 3

and for :

MyList=[1, 1, 1, 1, 1, 2, 3, 4, 5, 6]

and the output must be:

1 2
1 3
1 4
1 5
1 6

I saw i can do it with a method called round-robin but i don't know how. Thank you for your help!

Answer 1

from itertools import cycle

A = [[1,2,3],[4,5,6],[7]]
B = [[8],[9,10,11],[12,13]]

for p in A:
   max1 = len(p) if  max1 <len(p) else max1

for p in B:
   max1 = len(p) if  max1 <len(p) else max1

i = len(A)
j = 0
C = []
list_num = cycle(k for k in range(i))

for x in list_num:
   j += 1
   if j == i*3:
       break
   if A[x]:
       C.append(A[x].pop(0))
   if B[x]:
       C.append(B[x].pop(0))

Output:

[1, 8, 4, 9, 7, 12, 2, 5, 10, 13, 3, 6, 11]