N = int(input())
p = list(map(int, input().split()))

q = []
count = len(p) // 2
for _ in range(count):
    min_p = min(p[:-1])
    index = p.index(min_p)
    q.append(p.pop(index))
    q.append(p.pop(index))

ans = ' '.join([str(v) for v in q])
print(ans)