func_code_string: #include <bits/stdc++.h>   using namespace std;   const long long mod = 1000000007;   const long long inf = LLONG_MAX;   void IO() {     ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);     cout.setf(ios::fixed);     srand(chrono::high_resolution_clock::now().time_since_epoch().count());   }   long long pw(long long x, long long y, long long p = inf) {     long long res = 1;     x = x % p;     if (x == 0) return 0;     while (y > 0) {       if (y & 1) res = (res * x) % p;       y = y >> 1;       x = (x * x) % p;     }     return res;   }   long long invmod(long long a, long long m) { return pw(a, m - 2, m); }   long long cl(long long a, long long x) {     return a % x == 0 ? a / x : a / x + 1;   }   long long gcd(long long a, long long b) {     if (a == 0) return b;     return gcd(b % a, a);   }   void run_time_terror() {     long long n;     cin >> n;     cout <<  ? 1 3  << endl;     long long a, b;     cin >> a;     vector<long long> ans(n);     cout <<  ? 2 3  << endl;     cin >> b;     ans[0] = a - b;     for (long long i = 0; i < n - 1; ++i) {       long long x;       if (i == 1) {         x = b;       } else {         cout <<  ?   << i + 1 <<     << i + 2 << endl;         cin >> x;       }       ans[i + 1] = x - ans[i];     }     cout <<  !  ;     for (long long i = 0; i < n; ++i) {       cout << ans[i] <<    ;     }   }   int32_t main() {     cout << setprecision(0);     long long tt = 1;     for (long long case_no = 1; case_no <= tt; case_no++) {       run_time_terror();     }     return 0;   }   