Drawing diagrams helps. Here's your linked list:
Copy[ ]
|
v
[ ]
|
V
[ ]
|
V
None
Each arrow leading from a box represents the next attribute of that node.
Here are the three variables a, b, and c:
Copy [ ] <-- a
|
v
[ ] <-- b
|
V
[ ] <-- c
|
V
None
Each of these variables also points to a particular node.
If you say b.next = None, the next attribute of the node referenced by b is modified, like this:
Copy [ ] <-- a
|
v
None <-- [ ] <-- b
[ ] <-- c
|
V
None
This modifies the structure of the list. If you just set b itself to a different value, though, this is what happens:
Copy [ ] <-- a
|
v
None <-- [ ] b --> None
[ ] <-- c
|
V
None
You changed b, but the node that b used to point to stays right where it was. Note that this is similar to how the c node continued to exist even after you set b.next = None.
https://m.youtube.com/watch?v=lvO88XxNAzs
I love Python, it’s my first language and the language that got me into FAANG (interviews and projects).
It’s not my day to day language (now TypeScript) but I definitely think it’s the best for interviews and getting started which is why I used it in this video.
Included a ton of Python tips, as well as programming and software engineering knowledge. Give a watch if you want to improve on these and problem solving skills too 🫡
Videos
Drawing diagrams helps. Here's your linked list:
Copy[ ]
|
v
[ ]
|
V
[ ]
|
V
None
Each arrow leading from a box represents the next attribute of that node.
Here are the three variables a, b, and c:
Copy [ ] <-- a
|
v
[ ] <-- b
|
V
[ ] <-- c
|
V
None
Each of these variables also points to a particular node.
If you say b.next = None, the next attribute of the node referenced by b is modified, like this:
Copy [ ] <-- a
|
v
None <-- [ ] <-- b
[ ] <-- c
|
V
None
This modifies the structure of the list. If you just set b itself to a different value, though, this is what happens:
Copy [ ] <-- a
|
v
None <-- [ ] b --> None
[ ] <-- c
|
V
None
You changed b, but the node that b used to point to stays right where it was. Note that this is similar to how the c node continued to exist even after you set b.next = None.
Python doesn't have double pointers e.g. **x
Copyb.next = c
print(a) # a is 1 -> 2 -> 3
b.next = None
E.g. in above, it doesn't mean c is None
When a.next is b, if you change a.next.next you are effectively changing b.next
But if you change a.next to None, it will not set b to None
Edit:
Also when you set b = None but a.next still points ListNode(2)
Turns out the solution to this is to use: nums[:] = nums[newIndex+1:len(nums)] + nums[0:newIndex+1].
Doing nums = nums[newIndex+1:len(nums)] + nums[0:newIndex+1] simply changes the reference, while nums[:] changes the values of the list.
You can use
sudo service network-manager restart