N=int(input())
player=[x for x in range(N)]
opponent=[[] for x in range(N)]
while len(player)>=2:
    prev=player
    player=[]
    while len(prev)>=2:
        x,y=prev.pop(),prev.pop()
        print("?",x+1,y+1)
        ans=int(input())-1
        player.append(ans)
        opponent[ans].append(x^y^ans)
    if prev:
        player.append(prev.pop())
first=player[0]
player=opponent[first]
while len(player)>=2:
    prev=player
    player=[]
    while len(prev)>=2:
        x,y=prev.pop(),prev.pop()
        print("?",x+1,y+1)
        ans=int(input())-1
        player.append(ans)
    if prev:
        player.append(prev.pop())
ans=player[0]
print("!",ans+1)