Submission #470550

#	Time	Username	Problem	Language	Result	Execution time	Memory
470550		cp_is_hard	Colors (BOI20_colors)	C++14	0 / 100	1 ms	200 KiB

Colors

#define wiwihorz
#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma loop-opt(on)

#define rep(i, a, b) for(int i = a; i <= b; i++)
#define rrep(i, a, b) for(int i = b; i >= a; i--)
#define all(x) x.begin(), x.end()
#define ceil(a, b)

using namespace std;

#define INF 1000000000000000000
#define lld long double
#define int long long int
#define pii pair<int, int>
#define random mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count())

#ifdef wiwihorz
#define print(a...) kout("[" + string(#a) + "] = ", a)
void vprint(auto L, auto R) { while(L < R) cerr << *L << " \n"[next(L) == R], ++L;}
void kout() { cerr << endl; }
template<class T1, class ... T2> void kout(T1 a, T2 ... e) { cerr << a << " ", kout(e...); }
#else 
#define print(...)
#define vprint(...)
#endif
namespace solver {
	set<int> s;
	const int key = 71;
	int cur = -1, cnt;
	bool query(int p) {
		cout << "? " << p << endl;
		int x; cin >> x;
//		x = (cur == -1 ? 0 : abs(p - cur) >= key);
//		cur = p;
//		cnt ++;
		return x;
	}
	void ans(int x) {
		cout << "= " << x << endl;
	}
	void solve(int n) {
		cnt = 0;
		int dn = n + !(n & 1);
		int v = (1 + n) / 2;
		int L = 0, R = ((n & 1) ? v : v - 1);
		while(R - L > 1) {
			int mid = (L + R) / 2;
			s.insert(v - mid);
			s.insert(v + mid);
			query(v - mid);
			bool ans = query(v + mid);
			if(ans) R = mid;
			else L = mid;
		}
		// ans is 2 * L + 1 or 2 * L +  2;
		if(2 * L + 2 > n) ans(2 * L + 1);
		else {
			int ll = 1;
			while(s.find(ll) != s.end() ||
				s.find(ll + 2 * L + 1) != s.end()) ll++;
			query(ll);
			if(query(ll + 2 * L + 1)) ans(2 * L + 1);
			else ans(2 * L + 2);
		}
	}
};
using namespace solver;
signed main() {
	ios::sync_with_stdio(false), cin.tie(0);
	int n; cin >> n;
	solve(n);
	return 0;
}

Compilation message (stderr)

Colors.cpp:4: warning: ignoring '#pragma loop ' [-Wunknown-pragmas]
    4 | #pragma loop-opt(on)
      | 
Colors.cpp:21:13: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
   21 | void vprint(auto L, auto R) { while(L < R) cerr << *L << " \n"[next(L) == R], ++L;}
      |             ^~~~
Colors.cpp:21:21: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
   21 | void vprint(auto L, auto R) { while(L < R) cerr << *L << " \n"[next(L) == R], ++L;}
      |                     ^~~~
Colors.cpp: In function 'void solver::solve(long long int)':
Colors.cpp:45:7: warning: unused variable 'dn' [-Wunused-variable]
   45 |   int dn = n + !(n & 1);
      |       ^~

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