#include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; #define REP(i, n) for(int i = 0; i < (int)(n); i++) #define FOR(i,n,m) for (int i=n; i<(int)(m); i++) #define INF 1000000007 typedef long long ll; typedef long double ld; ll dy[4]={-1,1,0,0}; ll dx[4]={0,0,1,-1}; int main(){ int ub = 1000; int lb = 0; bool ans=false; while(ub - lb > 1){ int mid = (ub+lb)/2; cout << "? " << mid << endl; cin >> ans; if(ans) lb=mid; else ub=mid; } cout << "! " << lb << endl; return 0; }