Submission #540894

#	Time	Username	Problem	Language	Result	Execution time	Memory
540894		skittles1412	Colors (BOI20_colors)	C++17	0 / 100	1 ms	208 KiB

Colors

#include "bits/extc++.h"

using namespace std;

template <typename T>
void dbgh(const T& t) {
	cerr << t << endl;
}

template <typename T, typename... U>
void dbgh(const T& t, const U&... u) {
	cerr << t << " | ";
	dbgh(u...);
}

#ifdef DEBUG
#define dbg(...)                                           \
	cerr << "L" << __LINE__ << " [" << #__VA_ARGS__ << "]" \
		 << ": ";                                          \
	dbgh(__VA_ARGS__)
#else
#define cerr   \
	if (false) \
	cerr
#define dbg(...)
#endif

#define endl "\n"
#define long int64_t
#define sz(x) int((x).size())

int n;

bool valid(int x) {
	return 1 <= x && x <= n;
}

int dfs(int l, int r) {
	if (l == r) {
		return 1;
	}
	int mid = (l + r) / 2;
	int x = dfs(mid + 1, r);
	if (valid(x - mid)) {
		return x - mid;
	} else {
		return x + mid;
	}
}

void solve(int l, int r, int prev) {
	if (l == r) {
		cout << "= " << l << endl;
		return;
	}
	int mid = (l + r) / 2;
	int nxt = prev - mid;
	if (!valid(nxt)) {
		nxt = prev + mid;
	}
	cout << "? " << nxt << endl;
	int x;
	cin >> x;
	if (x) {
		solve(l, mid, nxt);
	} else {
		solve(mid + 1, r, nxt);
	}
}

void solve() {
	cin >> n;
	int start = dfs(1, n);
	dbg(start);
	cout << "? " << start << endl;
	int x;
	cin >> x;
	solve(1, n, start);
}

int main() {
	ios_base::sync_with_stdio(false);
	cin.exceptions(ios::failbit);
	solve();
}

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