#include <bits/stdc++.h>
using namespace std;
string s;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  while (cin >> s) {
    if (s == "end") break;
    int l = 0, r = 1;
    cout << "? " << 0 << " " << 1 << endl;
    cout.flush();
    string str;
    cin >> str;
    if (str == "x")
      l = 0, r = 1;
    else {
      for (int i = (0); i <= (29); i++) {
        cout << "? " << (1ll << i) << " " << (1ll << (i + 1)) << endl;
        cout.flush();
        string str;
        cin >> str;
        if (str == "x") {
          l = (1ll << i), r = (1ll << (i + 1));
          break;
        }
      }
    }
    while (r - l > 1) {
      int mid = (l + r) / 2;
      cout << "? " << l << " " << mid << endl;
      cout.flush();
      string str;
      cin >> str;
      if (str == "x")
        r = mid;
      else
        l = mid;
    }
    cout << "! " << r << endl;
    cout.flush();
  }
}
