a = []

while 1:

   d = int(input())

   if d == 0:

       break

   a.append(d)

n = int(input("Введите n: "))

if a.index(n) == 0:

   print(a[1])

elif a[a.index(n) - 1] < a[a.index(n) + 1]:

   print(a[a.index(n) - 1])

else:

   print(a[a.index(n) + 1])