#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#define X first
#define Y second
#define pb push_back

int main() {
	ios_base::sync_with_stdio(0), cin.tie(0);
	string str;
	while(cin >> str) {
		if (str == "end") break;
		ll k = 0;
		string ttr;
		cout << "? " << 0 << ' ' << 1 << endl;
		cin >> ttr;
		if (ttr == "x") {
			cout << "! " << 1 << endl;
			continue;
		}
		cout << "? " << (1LL << k) << ' ' << (1LL << (k + 1)) << endl;
		while(cin >> ttr) {
			if (ttr == "x") break;
			++k;
			cout << "? " << (1LL << k) << ' ' << (1LL << (k + 1)) << endl;
		}
		ll l = (1LL << k), r = (1LL << (k + 1));
		ll st = (1LL << k);
		ll out = 1;
		while(r - l > 1) {
			ll m = (l + r) / 2;
			cout << "? " << l << ' ' << m << endl;
			cin >> ttr;
			if (ttr == "x")
				r = m;
			else
				l = m;
		}
		cout << "! " << r << endl;
	}
	return 0;
}