完全二叉树小顶堆插入和删除节点，非递归，binarytree，Python

Posted 2021-12-19 zhangphil

完全二叉树小顶堆插入和删除节点，非递归，binarytree，Python

import binarytree
from binarytree import heap, get_parent


def app():
    # 构建一个小顶堆
    hp = heap(height=3, is_max=False, is_perfect=False)
    print(hp)

    print('-')
    # 在堆中插入一个节点
    values = hp.values
    values.append(99999)
    hp = binarytree.build(values)

    while not ok(hp):
        adjust(hp)

    print(hp)
    print('是小顶堆吗?', hp.is_min_heap)

    print('--')
    # 在堆中删除顶点（最小值）
    values = hp.values
    del (values[0])
    hp = binarytree.build(values)

    while not ok(hp):
        adjust(hp)

    print(hp)
    print('是小顶堆吗?', hp.is_min_heap)


def adjust(my_tree):
    nodes = my_tree.levelorder

    while len(nodes) != 0:
        node = nodes.pop()

        p = get_parent(my_tree, node)
        left = node.left
        right = node.right

        if left is not None:
            if left.value < node.value:
                swap(left, node)

        if right is not None:
            if right.value < node.value:
                swap(right, node)

        if p is not None:
            if node.value < p.value:
                swap(node, p)


def ok(my_tree):
    nodes = my_tree.levelorder

    done = True
    while len(nodes) != 0:
        p = nodes.pop()

        left = p.left
        right = p.right

        if left is not None:
            if p.value > left.value:
                done = False
                break

        if right is not None:
            if p.value > right.value:
                done = False
                break

    return done


# 交换节点的值
def swap(a, b):
    t = a.value
    a.value = b.value
    b.value = t


if __name__ == '__main__':
    app()

输出：

        _____0__
       /        \\
    __1___       2
   /      \\     / \\
  4       _8   6   12
 / \\     /
7   9   13

-

        ___________0__
       /              \\
    __1___             2
   /      \\           / \\
  4       _8__       6   12
 / \\     /    \\
7   9   13   99999

是小顶堆吗? True
--

         ________1___
        /            \\
    ___2______       _4
   /          \\     /  \\
  8          __6   12   7
 / \\        /
9   13   99999

是小顶堆吗? True