n = int(input())
a = list(map(int, input().split()))

to_sort = a[::2]
not_sort = a[1::2]

to_sort.sort()

a = [0] * n
for i in range(n // 2):
    a[i * 2] = to_sort[i]
    a[i * 2 + 1] = not_sort[i]
if n % 2 == 1:
    a[-1] = to_sort[-1]

print(*a)