Trying to figure this out

Question

#!/usr/bin/python3
list0 = []
list1 = []
list2 = []
table = [list0, list1, list2]
count = 0
for t in table:
for i in range(4):
t.append(str((count * 4) + i + 1))
print(" ".join(t))
count += 1

I understand what the code is doing by adding items to the lists and then printing the contents of these lists. I’m a little confused making sense of the code in the ‘append’ line. Thanks

Answer 1

Handtrace it.

When t is list0, count is 0:

0 * 4 + 0 + 1 = 1
0 * 4 + 1 + 1 = 2
0 * 4 + 2 + 1 = 3
0 * 4 + 3 + 1 = 4

When t is list1, count is 1:

1 * 4 + 0 + 1 = 5
1 * 4 + 1 + 1 = 6
1 * 4 + 2 + 1 = 7
1 * 4 + 3 + 1 = 8

When t is list2, count is 2:

2 * 4 + 0 + 1 = 9
2 * 4 + 1 + 1 = 10
2 * 4 + 2 + 1 = 11
2 * 4 + 3 + 1 = 12