heap.py

def parent(i):
    return (i + 1) / 2 - 1

def left(i):
    return (i + 1) * 2 - 1

def right(i):
    return ((i + 1) * 2)

def insert(heap, n):
    heap.append(n)
    i = len(heap) - 1

    while n < heap[parent(i)]:
        heap[i] = heap[parent(i)]
        i = parent(i)
        heap[i] = n

def delete_min(heap):
    heap[0], heap[-1] = heap[-1], heap[0]
    heap_min = heap.pop()
    i = 0

    while (heap[i] > heap[left(i)] or heap_min > heap[right(i)]) and heap[left(i)] != None and heap[right(i)] != None:
        if heap[left(i)] < heap[right(i)]:
            heap[left(i)], heap[i] = heap[i], heap[left(i)]
            i = left(i)
        else:
            heap[right(i)], heap[i] = heap[i], heap[right(i)]
            i = right(i)

        if left(i) >= len(heap) or right(i) >= len(heap):
            if left(i) >= len(heap):
                break
            else:
                if heap[i] > heap[left(i)]:
                    heap[left(i)], heap[i] = heap[i], heap[left(i)]
                break


    return heap_min

heap = [2, 5, 4, 11, 14, 10, 6, 12, 25, 15]

insert(heap, 3)
assert heap == [2, 3, 4, 11, 5, 10, 6, 12, 25, 15, 14]

assert delete_min(heap) == 2
assert heap == [3, 5, 4, 11, 14, 10, 6, 12, 25, 15]