#include <bits/stdc++.h>
using namespace std;
char ask(int a, int b) {
  cout << "? " << a << " " << b << endl;
  fflush(stdout);
  char t;
  cin >> t;
  return t;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  string s;
  while (cin >> s) {
    if (s == "end" || s == "mistake") {
      return 0;
    }
    if (ask(0, 1) == 'x') {
      cout << "! " << 1 << endl;
      fflush(stdout);
      continue;
    }
    int jk = 0;
    long long int a = 1, b = 2;
    int n = 1;
    long long int ans = 0;
    while (n < 30) {
      char ab = ask(a, b);
      if (ab == 'x') {
        char t = ask(0, b);
        if (t == 'x') {
          cout << "! " << b << endl;
          fflush(stdout);
          jk = 1;
          break;
        }
        ans = a;
        break;
      }
      a *= 2;
      b *= 2;
      if (b > 536870912) {
        ans = 536870912;
        break;
      }
      n++;
    }
    if (jk == 1) {
      continue;
    }
    long int temp = 0;
    a = a / 2;
    while (a > 0) {
      char ab = ask(temp + a, b);
      if (ab == 'x') {
        ans += a;
      } else {
        temp += a;
      }
      a = a / 2;
    }
    cout << "! " << ans << endl;
    fflush(stdout);
  }
}
