#include <iostream>
#include <vector>
#include <string>

using namespace std;

int main() {
    int N;
    cin >> N;

    vector<long long> P(N - 1);
    for (int i = 0; i < N - 1; ++i) {
        cout << "? " << i << " " << N - 1 << endl;
        cin >> P[i];
        if (P[i] == -1) return 0;
    }

    vector<string> candidates;
    for (int k = 1; k <= 9; ++k) {
        string current_x = "";
        bool ok = true;
        for (int i = 0; i < N - 1; ++i) {
            if (P[i] % k != 0 || P[i] / k > 9) {
                ok = false;
                break;
            }
            current_x += to_string(P[i] / k);
        }
        
        if (ok) {
            string full_x = "";
            full_x += to_string(k); 
            for (int i = N - 2; i >= 0; --i) {
                full_x += current_x[i];
            }
            string candidate = "";
            candidate += to_string(k);
            for(int i = N - 2; i >= 0; --i) {
                candidate += to_string(P[i] / k);
            }
            candidates.push_back(candidate);
        }
    }

    if (candidates.size() == 1) {
        cout << "! " << candidates[0] << endl;
    } else {
        cout << "! -1" << endl;
    }

    return 0;
}