blob: 5662d382269d3983bef3b4df913c208adc5a7aaa (
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class Node:
def __init__(self, data=None):
self.data = data
self.next = None
class LinkedList:
def __init__(self):
self.head = None
def append(self, data):
if not self.head:
self.head = Node(data)
else:
cur = self.head
while cur.next:
cur = cur.next
cur.next = Node(data)
def remove_from_end(self, n):
if self.head is None:
return
size = 0
cur = self.head
while cur:
size += 1
cur = cur.next
if n >= size:
self.head = self.head.next if self.head.next else None
else:
cur = self.head
for _ in range(size - n - 1):
cur = cur.next
cur.next = cur.next.next if cur.next and cur.next.next else None
def __str__(self):
values = []
cur = self.head
while cur:
values.append(str(cur.data))
cur = cur.next
return ' -> '.join(values)
# Tests
ll = LinkedList()
for i in range(1, 6):
ll.append(i)
for i in range(1, 7):
ll.remove_from_end(i)
print(ll)
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