n=int(input())
rui=1
for i in range(1,10):
    rui*=2
    if rui>=n:
        break
kekka=[[-1]*i for _ in range(n+1)]
#print(kekka)
member=[x for x in range(1,n+1)]
i=0
while len(member)>1:
    nm = []
    for a,b in zip(member[::2],member[1::2]):
        print("?",a,b)
        w=int(input())
        if w==b:a,b=b,a
        nm.append(a)
        kekka[a][i]=b
    if len(member)%2:
        nm.append(member[-1])
    member=nm
    i+=1

#print(kekka)
#print(member)

winner=member[0]
member=kekka[winner]

while len(member)>1:
    nm = []
    for a,b in zip(member[::2],member[1::2]):
        print("?",a,b)
        w=int(input())
        if w==b:a,b=b,a
        nm.append(a)
    if len(member)%2:
        nm.append(member[-1])
    member=nm
    i+=1

print(member[0])