#include <iostream>
#define rep(i, n) for(i = 0; i < n; i++)
using namespace std;

int query(int x, int y, int n) {
	if (y < 0 || y >= n) return x;
	if (x < 0 || x >= n) return y;
	cout << "? " << x + 1 << " " << y + 1 << endl;
	int ret;
	cin >> ret;
	return ret - 1;
}

const int DEPTH = 9;
int seg[1 << (DEPTH + 1)];

void init(int n) {
	int i;
	rep(i, (1 << (DEPTH + 1))) seg[i] = -1;
	rep(i, n) seg[(1 << DEPTH) - 1 + i] = i;
}

int construct(int n, int a = 0, int b = (1 << DEPTH), int id = 0) {
	if (b - a == 1) {
		return seg[id];
	}
	int u = construct(n, a, (a + b) / 2, id * 2 + 1);
	int v = construct(n, a, (a + b) / 2, id * 2 + 2);
	int res = query(u, v, n);
	seg[id] = res;
	return res;
}

int update(int pos, int val, int n) {
	pos += (1 << DEPTH) - 1;
	seg[pos] = val;
	while (pos > 0) {
		pos = (pos - 1) / 2;
		int res = query(seg[pos * 2 + 1], seg[pos * 2 + 2], n);
		seg[pos] = res;
	}
	return seg[0];
}

int main() {
	int n;
	cin >> n;
	init(n);
	int winner = construct(n);
	int ans = update(winner, -1, n);
	cout << "! " << ans + 1 << endl;
	return 0;
}