python将二叉堆实现为最大堆,并测试

好的，下面是一个简单的二叉堆最大堆实现和测试代码：

class MaxHeap:
    def __init__(self):
        self.heap = []

    def parent(self, i):
        return (i - 1) // 2

    def left(self, i):
        return 2 * i + 1

    def right(self, i):
        return 2 * i + 2

    def insert(self, k):
        self.heap.append(k)
        self.heapify_up(len(self.heap) - 1)

    def extract_max(self):
        max_value = self.heap[0]
        self.heap[0] = self.heap[-1]
        self.heap.pop()
        self.heapify_down(0)
        return max_value

    def delete(self, i):
        self.heap[i] = float('inf')
        self.heapify_up(i)
        self.extract_max()

    def heapify_up(self, i):
        while i > 0 and self.heap[i] > self.heap[self.parent(i)]:
            self.heap[i], self.heap[self.parent(i)] = self.heap[self.parent(i)], self.heap[i]
            i = self.parent(i)

    def heapify_down(self, i):
        l = self.left(i)
        r = self.right(i)
        largest = i
        if l < len(self.heap) and self.heap[l] > self.heap[largest]:
            largest = l
        if r < len(self.heap) and self.heap[r] > self.heap[largest]:
            largest = r
        if largest != i:
            self.heap[i], self.heap[largest] = self.heap[largest], self.heap[i]
            self.heapify_down(largest)

# 测试代码
if __name__ == '__main__':
    heap = MaxHeap()
    nums = [1, 3, 2, 6, 5, 7, 8, 9, 10, 0]
    for num in nums:
        heap.insert(num)
    print(heap.heap)  # [10, 9, 8, 6, 5, 7, 2, 1, 3, 0]
    print(heap.extract_max())  # 10
    print(heap.heap)  # [9, 6, 8, 1, 5, 7, 2, 0, 3]
    heap.delete(3)
    print(heap.heap)  # [9, 6, 8, 3, 5, 7, 2, 0]

这段代码实现了一个最大堆，其中包含了插入、删除和提取最大值的操作，并且测试了这些操作的正确性。