Submission #1111298

#	Time	Username	Problem	Language	Result	Execution time	Memory
1111298		thieunguyenhuy	Sphinx's Riddle (IOI24_sphinx)	C++17	10 / 100	36 ms	2120 KiB

sphinx

#ifndef hwe
	#include "sphinx.h"
#endif

#include <bits/stdc++.h>
using namespace std;

#define popcount(n) (__builtin_popcountll((n)))
#define clz(n) (__builtin_clzll((n)))
#define ctz(n) (__builtin_ctzll((n)))
#define lg(n) (63 - __builtin_clzll((n)))
#define BIT(n, i) (((n) >> (i)) & 1ll)
#define MASK(i) (1ll << (i))
#define FLIP(n, i) ((n) ^ (1ll << (i)))
#define ON(n, i) ((n) | MASK(i))
#define OFF(n, i) ((n) & ~MASK(i))

#define Int __int128
#define fi first
#define se second

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<long long, long long> pll;
typedef pair<long long, int> pli;
typedef pair<int, long long> pil;
typedef vector<pair<int, int>> vii;
typedef vector<pair<long long, long long>> vll;
typedef vector<pair<long long, int>> vli;
typedef vector<pair<int, long long>> vil;

template <class T1, class T2>
bool maximize(T1 &x, T2 y) {
    if (x < y) {
        x = y;
        return true;
    }
    return false;
}
template <class T1, class T2>
bool minimize(T1 &x, T2 y) {
    if (x > y) {
        x = y;
        return true;
    }
    return false;
}

template <class T>
void remove_duplicate(vector<T> &ve) {
    sort (ve.begin(), ve.end());
    ve.resize(unique(ve.begin(), ve.end()) - ve.begin());
}

mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
template <class T> T random(T l, T r) {
    return uniform_int_distribution<T>(l, r)(rng);
}
template <class T> T random(T r) {
    return rng() % r;
}

const int N = 1e6 + 5;
const int MOD = 1e9 + 7;
const int inf = 1e9;
const long long INF = 1e18;

#ifdef hwe
int perform_experiment(vector<int> E);
#endif

namespace sub12 {
	vector<int> find_colours(int n, vector<int> X, vector<int> Y) {
		vector<int> g(n, -1);
		for (int i = 0; i < n; ++i) {
			for (int c = 0; c < n; ++c) {
				vector<int> E(n, c); E[i] = -1;
				int foo = perform_experiment(E);
				if (foo == 1) {
					g[i] = c;
					break;
				}
			}
		}

		return g;
	}
}

namespace sub3 {
	struct DSU {
		vector<int> lab;

		DSU() {}

		void resize(int n) {
			lab.assign(n + 1, -1);
		}

		int find_set(int p) {
			return lab[p] < 0 ? p : lab[p] = find_set(lab[p]);
		}

		bool join(int u, int v) {
			u = find_set(u), v = find_set(v);
			if (u != v) {
				if (lab[u] > lab[v]) swap(u, v);
				lab[u] += lab[v], lab[v] = u;
				return true;
			}
			return false;
		}
	};

	vector<int> find_colours(int n, vector<int> X, vector<int> Y) {
		int m = X.size(); vector<int> g(n, 0), ans(n, 0);
		for (int i = 0; i < m; ++i) {
			vector<int> E(n, n); E[i] = E[i + 1] = -1;
			int foo = perform_experiment(E);
			if (foo == 1 + (i > 0) + (i + 1 < m)) g[i + 1] = g[i];
			else g[i + 1] = !g[i];
		}

		for (int l = 0, r = 0; l < n; l = r + 1) {
			while (r + 1 < n && g[r + 1] == g[l]) ++r;

			auto check = [&](int mid) {
				int pmid = l + 2 * mid + 1, expect = 2 * (mid + 1) + (pmid < r);
				vector<int> E(n, -1);
				for (int i = 0; i <= mid; ++i) E[l + 2 * i + 1] = i;
				int foo = perform_experiment(E);
				return foo != expect;
			};

			int low = 0, high = (r - l - 1) / 2, colour = -1;
			while (low <= high) {
				int mid = low + high >> 1;
				if (check(mid)) high = (colour = mid) - 1;
				else low = mid + 1;
			}
			assert(colour != -1);

			for (int i = l; i <= r; ++i) ans[i] = colour;
		}

		for (int i = 0; i < n; ++i) for (int j = i + 1; j < n; ++j) {
			if (ans[i] == ans[j]) {
				assert(g[i] == g[j]);
			}
		}

		return ans;
	}
}

vector<int> find_colours(int n, vector<int> X, vector<int> Y) {
	if (n <= 50) return sub12::find_colours(n, X, Y);

	int m = X.size();
	if (m == n - 1) return sub3::find_colours(n, X, Y);
}

#ifdef hwe
signed main() {
    ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);



    cerr << '\n'; return 0;
}
#endif

Compilation message (stderr)

sphinx.cpp: In function 'std::vector<int> sub3::find_colours(int, std::vector<int>, std::vector<int>)':
sphinx.cpp:139:19: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  139 |     int mid = low + high >> 1;
      |               ~~~~^~~~~~
sphinx.cpp: In function 'std::vector<int> find_colours(int, std::vector<int>, std::vector<int>)':
sphinx.cpp:163:1: warning: control reaches end of non-void function [-Wreturn-type]
  163 | }
      | ^

• Subtask 0: 0 / 0
• Subtask 1: 3 / 3
• Subtask 2: 7 / 7
• Subtask 3: 0 / 33
• Subtask 4: 0 / 21
• Subtask 5: 0 / 36