#include <bits/stdc++.h>
using namespace std;
int a[50];
char s[105];
int main() {
  a[0] = 0, a[1] = 1;
  for (int i = 2; i < 50; i++) a[i] = a[i - 1] << 1;
  while (1) {
    scanf("%s", s);
    if (s[0] == 's') {
      int pos = 0;
      for (int i = 1; i <= 31; i++) {
        printf("? %d %d\n", a[i - 1], a[i]);
        fflush(stdout);
        scanf("%s", s);
        if (s[0] == 'x') {
          pos = i;
          break;
        }
      }
      int st = a[pos - 1], en = a[pos];
      while (en - st > 1) {
        int mid = en + st >> 1;
        printf("? %d %d\n", st, mid);
        fflush(stdout);
        scanf("%s", s);
        if (s[0] == 'x') {
          en = mid;
        } else
          st = mid;
      }
      printf("! %d\n", en);
      fflush(stdout);
    } else
      break;
  }
  return 0;
}
