Last active
March 19, 2021 14:32
-
-
Save JoshCheek/e3f965aa31101f28ad955086d0f89354 to your computer and use it in GitHub Desktop.
linked list in Python
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
import functools | |
class LList: | |
@classmethod | |
def fromArray(cls, array): | |
return functools.reduce(lambda ll, val: ll.append(val), array, cls()) | |
def __init__(self): self.isEmpty = True | |
def append(self, val): return LNode(val, self) | |
def __iter__(self): return self | |
def next(self): raise StopIteration | |
def __len__(self): return 0 | |
def __repr__(self): return 'LList()' | |
def __str__(self, pre='(', delim=''): return pre + ')' | |
class LNode: | |
def __init__(self, val, rest): | |
self.val = val | |
self.rest = rest | |
def append(self, val): | |
return LNode(self.val, self.rest.append(val)) | |
def __iter__(ll): | |
yield ll.val | |
for val in ll.rest: yield val | |
# is there not a way I can just pass execution to `ll.next`? | |
# I think this "for val in" thing means we've got a stack of iterators | |
# each yielding their value up through the stack to the top one which | |
# finally yields it to the the thing receiving it. | |
# In Ruby, you would do it like this: | |
# def each(&block) | |
# block.call val | |
# rest.each &block | |
# end | |
# where `block.call` is equivalent to `yield`, so you can pass the thing | |
# that is being yielded to. | |
def __len__(self): | |
return 1 + len(self.rest) | |
def __str__(self, pre='(', delim=''): | |
return pre + delim + str(self.val) + self.rest.__str__('', '->') | |
def __repr__(self): | |
return 'LNode({0!r}, {1!r})'.format(self.val, self.rest) | |
def show(ll): | |
print('ll = {0!r}'.format(ll)) | |
print('len(ll) # => {0}'.format(len(ll))) | |
print('print(ll) # => {0}'.format(ll)) | |
print('') | |
show(LList.fromArray([])) | |
show(LList.fromArray([11,22,33])) |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment