#include <bits/stdc++.h>   using namespace std;   long long fS(long long x) {     long long lo = 1, hi = x - 1, cn = 0, ans = -1, out = 1;     while (cn <= 80) {       if (cn & 1)         ans -= (lo + hi) / 2;       else         ans += (lo + hi) / 2;       lo = (lo + hi) / 2 + 1;       out = min(out, ans);       cn++;     }     return out;   }   int main() {     int t;     cin >> t;     while (t--) {       long long n;       cin >> n;       long long start = -fS(n);       cout <<  ?   << start << endl;       long long tr;       cin >> tr;       long long lo = 1LL, hi = n - 1LL, cn = 0LL, best = n, ans = start, x;       while (lo <= hi) {         long long mid = (lo + hi) / 2LL;         if (cn & 1)           ans -= mid;         else           ans += mid;         cout <<  ?   << ans << endl;         cin >> x;         if (x) {           hi = mid - 1LL;           best = mid;         } else {           lo = mid + 1LL;         }         cn++;       }       cout <<  =   << best << endl;     }   }   