#include<bits/stdc++.h>
using namespace std;
unsigned long long m,x,y;
int t;
int main(){
	cin>>t;
	fflush(stdout);
	while(t--){
		cout<<"? "<<400000000<<endl;fflush(stdout);
		cin>>x;
		if(x==-1)return 0;
		cout<<"? "<<399999999<<endl;fflush(stdout);
		cin>>y;
		if(y==-1)return 0;
	    m=(y-x)*400000000+x;
		cout<<"! "<<m<<endl;
	}
	return 0;
}