Submission #685875

#	Time	Username	Problem	Language	Result	Execution time	Memory
685875		null_awe	Colors (BOI20_colors)	C++14	0 / 100	0 ms	208 KiB

Colors

#include <iostream>
using namespace std;

#define int long long

int n, at;

bool qry(int x) {
  if (at <= n / 2) at += x;
  else at -= x;
  cout << "? " << at << endl;
  bool ans; cin >> ans;
  return ans;
}

int32_t main() {
  cin >> n;
  bool added = true;
  at = 1;
  int test = 0;
  for (int i = 62; i >= 0; --i) {
    int chg = test + (1LL << i);
    if (chg >= n) continue;
    if (!added) at += 1LL << i;
    added = !added, test = chg;
  }
  cout << "? " << at << endl;
  int tmp; cin >> tmp;
  int sum = 0;
  for (int i = 62; i >= 0; --i) {
    int chg = sum + (1LL << i);
    if (chg >= n) continue;
    if (!qry(chg)) sum = chg;
  }
  cout << "= " << sum + 1 << '\n';
  return 0;
}

• Subtask 1: 0 / 9
• Subtask 2: 0 / 13
• Subtask 3: 0 / 21
• Subtask 4: 0 / 24
• Subtask 5: 0 / 33