#include <bits/stdc++.h>
using namespace std;
#pragma GCC diagnostic ignored "-Wmissing-declarations"
inline bool get(int x, int y) {
  cout << "? " << x << ' ' << y << endl;
  char res;
  cin >> res;
  if (res == 'e') exit(0);
  return res == 'x';
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0), cout.tie(0);
  string s;
  while (cin >> s) {
    if (s == "end") break;
    if (s == "mistake") return 0;
    int l = 0;
    int r = 2;
    while (!get(r / 2, r)) {
      l = r;
      r *= 2;
    }
    while (r - l > 1) {
      int mid = (l + r) >> 1;
      if (get(mid - l, mid))
        r = mid;
      else
        l = mid;
    }
    if (r == 1 && !get(0, 1)) r = 2;
    cout << "! " << r << endl;
  }
}
