linkedlist_ctypes.py

from ctypes import *

class Cell(Structure):
    pass

Cell._fields_ = [
        ("val", c_int),
        ("next", POINTER(Cell))]

class LinkedList:
    def __init__(self, iterable=None):
        if iterable is None:
            pass
        else:
            pass

        self.length = 0
        self._head = None

    def __len__(self):
        return self.length

    def head(self):
        return self._head

    def append(self, val):
        p = self.head()
        new = Cell(val=val)

        if p is None:
            self._head = new
        else:
            for i in range(len(self)-1):
                p = p.next.contents

            p.next = pointer(new)

        self.length += 1

    def get(self, index):
        assert index < len(self)
        assert index >= 0

        p = self.head()
        while index > 0:
            p = p.next.contents
            index -= 1

        return p.val

    def __getitem__(self, n):
        self.get(n)


    def insert(self, index, val):
        assert index < len(self)
        assert index >= 0

        index -= 1
        p = self.head()
        while index > 0:
            p = p.next.contents
            index -= 1

        new = Cell()
        new.val = val
        new.next = p.next
        p.next = pointer(new)
        self.length += 1

    def remove(self, index):
        assert index < len(self)
        assert index >= 0

        index -= 1
        p = self.head()
        while index > 0:
            p = p.next.contents
            index -= 1

        p.next = p.next.contents.next
        self.length -= 1