from SLinkedList import SLinkedList
# Test code
if __name__ == '__main__':
List1 = SLinkedList()
List2 = SLinkedList()
List1.append(5)
List1.append(7)
List1.append(8)
List1.add_atindex(val=10, index=1)
print(List1)
List2.append_list(val_list=[20, 55, 84, 37])
print(List2)
print(List1 + List2)
print("--------------------")
print(List1)
print(List2)
print(List2 + List1)
print("--------------------")
List1 += 3
print(List1)
List1 -= 3
print(List1)
def kth_to_last_element(l_list, k):
p1 = p2 = l_list.head
for i in range(k):
if p2 is None:
return None
p2 = p2.next
while p2:
p1 = p1.next
p2 = p2.next
return p1
s = SLinkedList()
nums = [1, 2, 8, 6, 5, 2, 7, 6, 5, 9, 2, 10]
nums = [11, 22, 33]
for num in nums:
if not s.head:
s.head = Node(num)
curr = s.head
else:
n = Node(num)
curr.next = n
curr = n
while True:
# on the same node, a cycle exists
if slow == fast:
return True
# progress the slow pointer
slow = slow.next
# if fast
if fast.next and fast.next.next:
fast = fast.next.next
else:
return False
# -------------------------------------------------- #
s = SLinkedList()
s.head = Node(1)
n = s.head
for i in range(10):
n.next = Node(i)
# save node to create cycle
if i == 3:
loop_node = n
n = n.next
# cycle last node back in list
n.next = loop_node
print(has_cycle(s.head))
import sys
sys.path.append(r"C:\Users\Sasha\Coding\Algorithms and Data Structures\Algorithms in Python\LinkedList")
from SLinkedList import SLinkedList
def has_cycle(head):
"""Floyd's Cycle-Finding Algorithm.
Also known as Tortoise and Hare Algorithm."""
slow = head
fast = head
while fast and fast.next:
slow = slow.next
fast = fast.next.next
if slow is fast:
return True
return False
L = SLinkedList()
for i in range(1,8): L.add_start(i)
tmp = L.head
while tmp.next: tmp = tmp.next
tmp.next = L.head.next.next.next.next
print(has_cycle(L.head))
from SLinkedList import SLinkedList s = SLinkedList() s.insertAtHead(2) s.insertAtHead(3) s.insertAtTail(10) s.insertAtTail(12) s.deleteFromTail() s.deleteFromHead() s.print()
def __init__(self, *args, **kwargs):
super(TestSLinkedListMethods, self).__init__(*args, **kwargs)
self.x = SLinkedList()
class TestSLinkedListMethods(unittest.TestCase):
def __init__(self, *args, **kwargs):
super(TestSLinkedListMethods, self).__init__(*args, **kwargs)
self.x = SLinkedList()
def test_empty(self):
self.assertEqual(self.x.empty(), True)
def test_push_back(self):
self.x.push_back(10)
self.x.push_back(20)
self.x.push_back(30)
def test_front_back(self):
self.x.push_back(10)
self.x.push_back(20)
self.x.push_back(30)
self.assertEqual(self.x.front(), 10)
self.assertEqual(self.x.back(), 30)
def test_insert(self):
self.x.push_back(10)
self.x.push_back(20)
self.x.push_back(30)
self.assertEqual(self.x.front(), 10)
self.assertEqual(self.x.back(), 30)
def test_find(self):
self.x.push_back(10)
self.x.push_back(20)
self.x.push_back(30)
self.assertEqual(self.x.find(30).value, 30)