def __init__(self, arr=None, capacity=0):
if isinstance(arr, list):
self._data = Array(arr)
# heapify
for i in range((self.size() - 1) // 2, -1, -1):
self._sift_down(i)
else:
self._data = Array(capacity=capacity) if capacity else Array()
def test_set(self):
array = Array([1, 2, 3, 4, 5, 6, 7, 8])
try:
array.set(array.get_size(), 8)
except Exception as e:
self.assertTrue(isinstance(e, IndexError))
array.set(0, 10)
self.assertEqual(array.get_first(), 10)
def test_add_and_get(self):
array = Array([1, 2, 3])
try:
array.add(6, 4)
except Exception as e:
self.assertTrue(isinstance(e, IndexError))
array.add(1, 5)
self.assertEqual(array.get(1), 5)
try:
array.get(20)
except Exception as e:
self.assertTrue(isinstance(e, IndexError))
class ArrayStack:
def __init__(self, cap=0):
self._array = Array(capacity=cap)
def push(self, e):
self._array.add_last(e)
def pop(self):
return self._array.remove_last()
def peek(self):
return self._array.get_last()
def get_size(self):
return self._array.get_size()
def is_empty(self):
return self._array.is_empty()
def get_capacity(self):
return self._array.get_capacity()
def __str__(self):
return f"ArrayStack: {[self._array.get(i) for i in range(self.get_size())]}, right is top."
def __repr__(self):
return self.__str__()
class ArrayQueue:
def __init__(self, cap=0):
self._array = Array(capacity=cap)
def get_size(self):
return self._array.get_size()
def is_empty(self):
return self._array.is_empty()
def enqueue(self, e):
self._array.add_last(e)
def dequeue(self): # time complexity: O(n)
return self._array.remove_first()
def get_front(self):
return self._array.get_first()
def __str__(self):
return f"ArrayQueue: front {[self._array.get(i) for i in range(self.get_size())]} tail."
def __repr__(self):
return self.__str__()
def test_get_capacity(self):
array = Array()
self.assertEqual(array.get_capacity(), 0)
array.add_last(5)
self.assertEqual(array.get_capacity(), 1)
array.add_last(5)
self.assertEqual(array.get_capacity(), 2)
array.add_last(5)
self.assertEqual(array.get_capacity(), 4)
array.add_last(5)
self.assertEqual(array.get_capacity(), 4)
array.add_last(5)
self.assertEqual(array.get_capacity(), 8)
def test_remove(self):
array = Array([1, 2, 3, 4, 5, 6, 7, 8])
try:
array.remove(array.get_size())
except Exception as e:
self.assertTrue(isinstance(e, IndexError))
array.remove_last()
self.assertEqual(array.get_capacity(), 8)
array.remove_last()
self.assertEqual(array.get_capacity(), 8)
array.remove_last()
self.assertEqual(array.get_capacity(), 8)
array.remove_last()
self.assertEqual(array.get_capacity(), 8)
array.remove_last()
self.assertEqual(array.get_capacity(), 8)
array.remove_last()
self.assertEqual(array.get_capacity(), 4)
array.remove_last()
self.assertEqual(array.get_capacity(), 2)
array.remove_last()
self.assertEqual(array.get_capacity(), 1)
def test_remove_last(self):
array = Array([1, 2, 3])
array.remove_last()
self.assertEqual(array.find(3), -1)
def test_remove_element(self):
array = Array([1, 2, 3])
array.remove_element(2)
self.assertEqual(array.find(2), -1)
def test_contains_and_find(self):
array = Array([1, 2, 3])
self.assertTrue(array.contains(3))
self.assertFalse(array.contains(6))
self.assertEqual(array.find(2), 1)
self.assertEqual(array.find(6), -1)
def test_get_size(self):
array = Array([1, 2, 3])
self.assertEqual(array.get_size(), 3)
def test_add_first_and_get_first(self):
array = Array()
array.add_first(6)
self.assertEqual(array.get_first(), 6)
def test_is_empty(self):
array = Array()
self.assertTrue(array.is_empty())
def test_magic_repr(self):
array = Array([1, 2, 3])
self.assertEqual(repr(array), "Array: [1, 2, 3], capacity: 3")
def __init__(self, cap=0):
self._array = Array(capacity=cap)
class MaxHeap:
def __init__(self, arr=None, capacity=0):
if isinstance(arr, list):
self._data = Array(arr)
# heapify
for i in range((self.size() - 1) // 2, -1, -1):
self._sift_down(i)
else:
self._data = Array(capacity=capacity) if capacity else Array()
def size(self):
return self._data.get_size()
def is_empty(self):
return self._data.is_empty()
def add(self, e):
self._data.add_last(e)
self._sift_up(self.size() - 1)
def _sift_up(self, index):
while index > 0 and self._data.get(index) > self._data.get(
(index - 1) // 2):
self._data.swap(index, (index - 1) // 2)
index = (index - 1) // 2
def find_max(self):
if self.size() > 0:
return self._data.get_first()
def extract_max(self):
res = self.find_max()
self._data.swap(0, self.size() - 1)
self._data.remove_last()
self._sift_down(0)
return res
def _sift_down(self, index):
while 2 * index + 1 < self.size():
j = 2 * index + 1
if j + 1 < self.size() and self._data.get(j) < self._data.get(j +
1):
j += 1
if self._data.get(index) >= self._data.get(j):
break
self._data.swap(j, index)
index = j
def replace(self, e):
res = self.find_max()
self._data.set(0, e)
self._sift_down(0)
return res
