Submission #1303395

#	Time	Username	Problem	Language	Result	Execution time	Memory
1303395		_asunaa	Colors (BOI20_colors)	C++20	0 / 100	1 ms	424 KiB

Colors

#include <bits/stdc++.h>
using namespace std;
long long i, j, l, r, mid, p, q, k, t, n, m, a, b, c, d, ans, cnt, res;
const long long mod = 999993143, mod2 = 999993469;
string s;
bool check;
int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	cin >> n;
	a = 1;
	b = n;
	c = n / 2;
	l = 0;
	r = c - 1;
	t = -1;
	while (l <= r && a < b){
		mid = (l + r) / 2;
		if (n % 2 == 1 && mid == c - 1){
			cout << "? " << n << endl;
			cin >> d;
			if (t != -1){
				if (d == 0){
					a = max(a, abs(n - t) + 1);
				}
				else{
					b = min(b, abs(n - t));
				}
			}
			t = n;
			cout << "? " << 1 << endl;
			cin >> d;
			if (t != -1){
				if (d == 0){
					a = max(a, abs(1 - t) + 1);
				}
				else{
					b = min(b, abs(1 - t));
				}
			}
			t = 1;
			cout << "? " << n - 1 << endl;
			cin >> d;
			if (t != -1){
				if (d == 0){
					a = max(a, abs((n - 1) - t) + 1);
				}
				else{
					b = min(b, abs((n - 1) - t));
				}
			}
			break;
		}
		else{
			cout << "? " << c - mid << endl;
			cin >> d;
			if (t != -1){
				if (d == 0){
					a = max(a, abs((c - mid) - t) + 1);
				}
				else{
					b = min(b, abs((c - mid) - t));
				}
			}
			t = c - mid;
			cout << "? " << c + mid + 1 << endl;
			cin >> d;
			if (t != -1){
				if (d == 0){
					a = max(a, abs((c + mid + 1) - t) + 1);
					l = mid + 1;
				}
				else{
					b = min(b, abs((c + mid + 1) - t));
					r = mid - 1;
				}
			}
			t = c + mid + 1;
		}
	}
	cout << "= " << a << endl;
//	cout << "= " << b << endl;
}

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