Question

I have two list

list1 = [(100, A, 22), (200,B, 33), (300, C, 44)]

and

list2 = [(100,A,333), (200,B,444), (500, D, 555)]

so what I want as my final list is

final_list = [ (100,A, 22, 333), (200,B,33,444), (300,C,44,0), (500,D,0,555)]

If I just add the two list it wont help me out. How can i achieve the final list.

Thanks

Answer 1

Your input data should be dictionaries in the first place:

dict1 = {(100, "A"): 22, (200,"B"): 33, (300, "C"): 44}
dict2 = {(100, "A"): 333, (200,"B"): 444, (500, "D"): 555}

Now you can easily build a combined dict:

>>> {k: (dict1.get(k, 0), dict2.get(k, 0))
...  for k in dict1.viewkeys() | dict2.viewkeys()}
{(100, 'A'): (22, 333), (200, 'B'): (33, 444), 
 (300, 'C'): (44, 0), (500, 'D'): (0, 555)}

(Python 2.7)

If for some reason you need to operate on the lists, I’d suggest turning your lists into dictionaries first

dict1 = {(k1, k2): v for k1, k2, v in list1}
dict2 = {(k1, k2): v for k1, k2, v in list2}