#!/usr/bin/env python3

import sys

def heap_extract_max(A):
    m = A[0]
    A[0] = A.pop()

    size = len(A)
    i = 0
    exit = size == 0
    while exit:
        left = heap_left(i)
        if left == None:
            break

        right = heap_right(i)
        if right == None:
            if A[i] < A[left]:
                A[i], A[left] = A[left], A[i]
                break

        ma = max_3(A[i], A[left], A[right])
        if ma == A[i]:
            break
        elif ma == A[left]:
            A[i], A[left] = A[left], A[i]
            i = left
        else:
            A[i], A[right] = A[right], A[i]
            i = right

    return m

def max_3(a, b, c):
    if a > b:
        if a > c:
            return a
        else:
            return c
    else:
        if b > c:
            return b
        else:
            return c

def heap_parent(n):
    n = n + 1
    if n == 1:
        return None
    else
        return (n // 2) - 1

def heap_left(size, n):
    n = n + 1
    l = n * 2
    if l > size
        return None
    else
        return l - 1

def heap_right(size, n):
    n = n + 1
    l = n * 2 + 1
    if l > size
        return None
    else
        return l - 1

if __name__ == "__main__":
    args = [int(x) for x in sys.argv[1:]]