#include <bits/stdc++.h>
using namespace std;
const int MAXN = 15;
const long long MOD = 1e6 + 3;
long long get_inv(long long x) {
  long long pw = MOD - 2, res = 1;
  while (pw) {
    if (pw & 1) res = res * x % MOD;
    pw >>= 1;
    x = x * x % MOD;
  }
  return res;
}
vector<long long> gauss(int N, long long m[MAXN][MAXN + 1]) {
  for (int i = 0; i < N - 1; i++) {
    int r = i;
    for (int j = i; j < N; j++) {
      if (m[j][i] != 0) {
        r = j;
        break;
      }
    }
    if (m[r][i] == 0) continue;
    for (int j = 0; j < N + 1; j++) {
      swap(m[i][j], m[r][j]);
    }
    for (r = i + 1; r < N; r++) {
      long long mul = m[r][i] * get_inv(m[i][i]) % MOD;
      for (int c = 0; c < N + 1; c++) {
        m[r][c] = (m[r][c] - (long long)m[i][c] * mul) % MOD;
      }
    }
  }
  vector<long long> sol(N);
  for (int i = N - 1; i >= 0; i--) {
    long long val = m[i][N];
    for (int j = i + 1; j < N; j++) {
      val = (val - m[i][j] * sol[j]) % MOD;
    }
    if (m[i][i] == 0) {
      return vector<long long>();
    }
    sol[i] = (val * get_inv(m[i][i]) % MOD + MOD) % MOD;
  }
  return sol;
}
long long m[MAXN][MAXN + 1];
int main() {
  int N = 11;
  for (int i = 0; i < N; i++) {
    int pw = 1;
    for (int j = 0; j < N; j++) {
      m[i][j] = pw;
      pw = pw * i % MOD;
    }
    cout << "? " << i << endl;
    cin >> m[i][N];
  }
  int ans = -1;
  vector<long long> coe = gauss(N, m);
  for (long long i = 0; i < MOD; i++) {
    long long pw = 1, sum = 0;
    for (int j = 0; j < N; j++) {
      sum = (sum + pw * coe[j]) % MOD;
      pw = pw * i % MOD;
    }
    if (sum == 0) {
      ans = i;
      break;
    }
  }
  cout << "! " << ans << endl;
  return 0;
}
