from strutils import parseInt
from sequtils import mapIt

let N = stdin.readLine.parseInt

var participants = (1..N).mapIt(it)

proc ask(x, y: int): int =
  echo "? ", x, " ", y
  stdin.readLine.parseInt

var next = newSeq[int]()
while participants.len > 4:
  next = @[]
  for i in countup(1, participants.high, 2):
    let ans = ask(participants[i - 1], participants[i])
    next.add(ans)
  if participants.len mod 2 == 1:
    next.add(participants[^1])
  participants = next

doAssert participants.len > 1
if ask(participants[0], participants[1]) == participants[1]:
  swap(participants[0], participants[1])
case participants.len:
  of 2:
    discard
  of 3:
    if ask(participants[0], participants[2]) == participants[2]:
      swap(participants[0], participants[2])
    if ask(participants[1], participants[2]) == participants[2]:
      swap(participants[1], participants[2])
  of 4:
    if ask(participants[2], participants[3]) == participants[3]:
      swap(participants[2], participants[3])
    if ask(participants[0], participants[2]) == participants[2]:
      swap(participants[0], participants[2])
    if ask(participants[1], participants[2]) == participants[2]:
      swap(participants[1], participants[2])
  else:
    discard

echo "! ", participants[1]