Python Data Structures and Algorithms

Lists

Lists are probably the most used built-in data structures in Python because they can be composed of any number of other data types. They are a simple representation of arbitrary objects. Like strings, they are indexed by integers starting with zero. The following table contains the most commonly used list methods and their descriptions:

Method	Description
list(s)	Returns a list of the sequence s.
s.append(x)	Appends element x to the end of s.
s.extend(x)	Appends the list x to s.
s.count(x)	Counts the occurrence of x in s.
s.index(x, [start], [stop])	Returns the smallest index, i, where s[i] ==x. Can include optional start and stop index for the search.
s.insert(i,e)	Inserts x at index i.