#!/usr/bin/env python3
import random

n = int(input())

d = [(-1, 0), (0, 1), (1, 0), (0, -1)]


def q(x, y):
    if x < 1 or x > n or y < 1 or y > n:
        return -1
    print("?", x, y)
    return int(input())


x, y = n // 2, n // 2

# Sample n random points, and start at the best one.

best = 0

for i in range(10 * n):
    window = i // 10 + 1
    xi = random.randint(max(1, x - window), min(n, x + window))
    yi = random.randint(max(1, y - window), min(n, y + window))
    v = q(xi, yi)
    if v > best:
        best = v
        x, y = xi, yi
print("!", best)