尤其注意：
append,+,extend的区别
| Method/Function | Description | Example Input | Resulting List/Output |
|---|---|---|---|
append(x) |
Adds a single element x to the end of the list. |
[1, 2, 3].append(4) |
[1, 2, 3, 4] |
extend(iter) |
Adds all elements of an iterable iter to the end of the list. |
[1, 2, 3].extend([4, 5]) |
[1, 2, 3, 4, 5] |
insert(i, x) |
Inserts element x at index i. |
[1, 2, 3].insert(1, 10) |
[1, 10, 2, 3] |
remove(x) |
Removes the first occurrence of element x. |
[1, 2, 3, 2].remove(2) |
[1, 3, 2] |
pop([i]) |
Removes and returns the element at index i (defaults to the last element). |
[1, 2, 3].pop(1) |
2 (list becomes [1, 3]) |
clear() |
Removes all elements from the list. | [1, 2, 3].clear() |
[] |
index(x) |
Returns the index of the first occurrence of element x. |
[1, 2, 3, 2].index(2) |
1 |
count(x) |
Returns the number of occurrences of element x. |
[1, 2, 2, 3].count(2) |
2 |
sort() |
Sorts the list in ascending order (in-place). | [3, 1, 2].sort() |
[1, 2, 3] |
reverse() |
Reverses the elements of the list in-place. | [1, 2, 3].reverse() |
[3, 2, 1] |
copy() |
Returns a shallow copy of the list. | [1, 2, 3].copy() |
[1, 2, 3] (new list) |
len(list) |
Returns the number of elements in the list. | len([1, 2, 3]) |
3 |
sum(list) |
Returns the sum of all elements in the list. | sum([1, 2, 3]) |
6 |
min(list) |
Returns the smallest element in the list. | min([1, 2, 3]) |
1 |
max(list) |
Returns the largest element in the list. | max([1, 2, 3]) |
3 |
sorted(list) |
Returns a new sorted list (does not modify the original). | sorted([3, 1, 2]) |
[1, 2, 3] |
reversed(list) |
Returns a reverse iterator (use list() to convert to a list). |
list(reversed([1, 2, 3])) |
[3, 2, 1] |
list(iter) |
Converts an iterable (e.g., tuple, string) to a list. | list((1, 2, 3)) |
[1, 2, 3] |
del list[i] |
Deletes the element at index i. |
del [1, 2, 3][1] |
[1, 3] |
list[i:j] |
Slices the list from index i to j-1. |
[1, 2, 3, 4][1:3] |
[2, 3] |
list + list |
Concatenates two lists. | [1, 2] + [3, 4] |
[1, 2, 3, 4] |
list * n |
Repeats the list n times. |
[1, 2] * 2 |
[1, 2, 1, 2] |
标签：index,elements,python,list,element,Returns,sorted,操作 From： https://www.cnblogs.com/yama-lei/p/18652016