Python: Appending items to lists by iterating through list of lists

Question

I\'m a Python newbie crossing over from C. I\'m basically trying implement logic equivalent to an array of array pointers in C.

I want to append one item to the end

Answer 1

You only create one list

list1 = list2 = list3 = list()

this line creates an empty list, assigns its reference to list3, assigns reference to list3 to list2 and to list1, as a result these refer to the same object. So when you add your values, you add them to all of your "lists".

This will work just fine

data = [10, 20, 30]
lists = [[], [], []]

for i in range(len(data)):
    lists[i].append(data[i])

for lst in lists:
    print lst

But the simplest way would be to do just

data = [10, 20, 30]
lists = [ [x] for x in data ]