Submission #1200632

#	Time	Username	Problem	Language	Result	Execution time	Memory
1200632		thieunguyenhuy	Sphinx's Riddle (IOI24_sphinx)	C++17	18 / 100	31 ms	472 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 = 250 + 5;
const int MOD = 1e9 + 7;
const int inf = 1e9;
const long long INF = 1e18;

#ifdef hwe
namespace Jury {
	int n, m;
	vii edges;
	vector<int> color, adj[N];

	void test() {
		cin >> n >> m;

		for (int i = 0; i < n; ++i) adj[i].clear();

		color.assign(n, 0);
		for (auto &x : color) cin >> x;

		edges.assign(m, pii());
		for (auto &[x, y] : edges) {
			cin >> x >> y;
			adj[x].emplace_back(y), adj[y].emplace_back(x);
		}
	}

	int perform_experiment(vector<int> E) {
		vector<int> S = color;
		for (int i = 0; i < n; ++i)
			if (E[i] != -1) S[i] = E[i];
		vector<int> vis(n, false);
		int num_components = 0;
		for (int i = 0; i < n; ++i) if (!vis[i]) {
			queue<int> q; q.emplace(i);
			vis[i] = true; ++num_components;
			while (!q.empty()) {
				int u = q.front(); q.pop();
				for (auto v : adj[u]) if (!vis[v] && S[v] == S[i]) {
					vis[v] = true;
					q.emplace(v);
				}
			}
		}
		return num_components;
	}
}

int perform_experiment(vector<int> E) {
	return Jury::perform_experiment(E);
}
#endif

vector<int> adj[N];

namespace sub12 {
	vector<int> find_colours(int n, vector<int> X, vector<int> Y) {
		vector<int> ans(n, 0);
		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) {
					ans[i] = c;
					break;
				}
			}
		}

		return ans;
	}
}

namespace sub3 {
	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];
		}

		return g;

		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, color = -1;
			while (low <= high) {
				int mid = (low + high) >> 1;
				if (check(mid)) high = (color = mid) - 1;
				else low = mid + 1;
			}
			assert(color != -1);

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

		return ans;
	}
}

struct DSU {
	vector<int> lab;
	vector<vector<int>> components;

	DSU() {}

	void resize(int n) {
		lab.assign(n, -1);
		components.assign(n, vector<int>());
		for (int i = 0; i < n; ++i) components[i].emplace_back(i);	
	}

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

	bool same_set(int u, int v) {
		return find_set(u) == find_set(v);
	}

	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;
			for (auto &x : components[v]) components[u].emplace_back(x);
			return true;
		}
		return false;
	}
} dsu;

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

	// identify components
	for (int i = 0; i < X.size(); ++i) {
		int u = X[i], v = Y[i];
		adj[u].emplace_back(v), adj[v].emplace_back(u);
	}

	auto count = [&](vector<int> E) {
		vector<int> vis(n, false);
		int num_components = 0;
		for (int i = 0; i < n; ++i) if (E[i] == n && !vis[i]) {
			queue<int> q; q.emplace(i);
			vis[i] = true; ++num_components;
			while (!q.empty()) {
				int u = q.front(); q.pop();
				for (auto v : adj[u]) if (E[v] == n && !vis[v]) {
					vis[v] = true;
					q.emplace(v);
				}
			}
		}
		return num_components;
	};

	dsu.resize(n);
	for (int i = 1; i < n; ++i) {
		vector<int> roots;
		for (int j = 0; j < i; ++j) if (dsu.find_set(j) == j) {
			roots.emplace_back(j);
		}
		int low = 0, high = roots.size() - 1, rootId = -1;
		while (low <= high) {
			int mid = (low + high) >> 1;
			vector<int> E(n, n); E[i] = -1;
			for (int i = 0; i <= mid; ++i)
				for (auto &x : dsu.components[roots[i]]) E[x] = -1;
			if (perform_experiment(E) <= count(E) + mid + 1) high = (rootId = mid) - 1;
			else low = mid + 1;
		}
		if (rootId != -1) dsu.join(roots[rootId], i);
	}

	vii edges;
	for (int i = 0; i < X.size(); ++i) { 
		int u = X[i], v = Y[i];
		u = dsu.find_set(u), v = dsu.find_set(v);
		if (u == v) continue;
		if (u > v) swap(u, v);
		edges.emplace_back(u, v);
	}

	remove_duplicate(edges);
	assert(edges.size() < n);
	
	for (auto [u, v] : edges) {
		u = dsu.find_set(u), v = dsu.find_set(v);
		if (u == v) continue;
		vector<int> E(n, n);
		for (auto &x : dsu.components[u]) E[x] = -1;
		for (auto &x : dsu.components[v]) E[x] = -1;
		if (perform_experiment(E) < count(E) + 2) dsu.join(u, v);
	}

	vector<int> ans(n, 0);
	for (int i = 0; i < n; ++i) ans[i] = dsu.find_set(i);

	return ans;
}

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

	Jury::test();
	
	vector<int> X(Jury::m), Y(Jury::m);
	for (int i = 0; i < Jury::m; ++i) tie(X[i], Y[i]) = Jury::edges[i];

	vector<int> ans = find_colours(Jury::n, X, Y);
	for (auto &x : ans) cerr << x << ' ';
	cerr << '\n';

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

• Subtask 0: 0 / 0
• Subtask 1: 1.5 / 3
• Subtask 2: 0 / 7
• Subtask 3: 16.5 / 33
• Subtask 4: 0 / 21
• Subtask 5: 0 / 36