Submission #1063694

#	Time	Username	Problem	Language	Result	Execution time	Memory
1063694		pawned	Game (IOI14_game)	C++17	15 / 100	13 ms	18232 KiB

game

#pragma GCC optimize("O1,O2,O3,Ofast,unroll-loops")

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

#define fi first
#define se second
#define pb push_back
typedef long long ll;
typedef pair<ll, ll> ii;
typedef vector<ll> vi;

#include "game.h"

struct DSU {
	vi e;
	void init(int N) {
		e = vi(N, -1);
	}
	int root(int x) {
		if (e[x] < 0) {
			return x;
		}
		else {
			e[x] = root(e[x]);
			return e[x];
		}
	}
	bool sameset(int x, int y) {
		return(root(x) == root(y));
	}
	bool merge(int x, int y) {
		x = root(x);
		y = root(y);
		if (x == y)
			return false;
		if (-e[x] < -e[y])
			swap(x, y);
		e[x] += e[y];
		e[y] = x;
		return true;
	}
	int size(int x) {
		return -e[root(x)];
	}
};

const int MAX = 1505;

int N;

DSU dsu;
int ccs;

vector<vi> adj(MAX, vi(MAX, 0));
// 0 if not done
// 1 if missing
// 2 if filled

void initialize(int n) {
	N = n;
	dsu.init(N);
	ccs = N;
}

int hasEdge(int u, int v) {
/*	cout<<"adj: "<<endl;
	for (int i = 0; i < N; i++) {
		for (int j = 0; j < N; j++) {
			cout<<adj[i][j]<<" ";
		}
		cout<<endl;
	}
	cout<<"ccs: "<<ccs<<endl;*/
	// check if connecting u to v makes any "bad triangle"
	// bad triangle u, v, w if (u, v) = 2, (u, w) = 2, and (v, w) isn't 1
	// or if (v, w) = 2 and (u, w) isn't 1
	bool can = true;
	for (int i = 0; i < N; i++) {
		if (adj[u][i] == 2 && adj[v][i] != 1)
			can = false;
		if (adj[v][i] == 2 && adj[u][i] != 1)
			can = false;
	}
	if (can && ccs >= 3) {
		adj[u][v] = 2;
		adj[v][u] = 2;
		if (!dsu.sameset(u, v)) {
			dsu.merge(u, v);
			ccs--;
		}
		return 1;
	}
	else {
		adj[u][v] = 1;
		adj[v][u] = 1;
		return 0;
	}
}

• Subtask 1: 15 / 15
• Subtask 2: 0 / 27
• Subtask 3: 0 / 58