#include <bits/stdc++.h>
using namespace std;
char ask(int x, int y) {
  char t;
  printf("? %d %d\n", x, y);
  fflush(stdout);
  cin >> t;
  return t;
}
int main() {
  string s;
  while (cin >> s) {
    if (s == "end") break;
    int l = 0, r = 1;
    while (ask(l, r) == 'y') {
      l = r;
      r *= 2;
    }
    while (l + 1 < r) {
      int mid = (l + r) / 2;
      if (ask(mid, r) == 'x')
        l = mid;
      else
        r = mid;
    }
    printf("! %d\n", r);
    fflush(stdout);
  }
  return 0;
}
