제출 #1291645

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1291645		lucaskojima	슈퍼트리 잇기 (IOI20_supertrees)	C++17	11 / 100	95 ms	22028 KiB

supertrees

#include "bits/stdc++.h"
#include "supertrees.h"
#define sz(x) (int)size(x)
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)

using namespace std;
using ll = long long;
using pii = pair<int, int>;

const char nl = '\n';
const int INF = 0x3f3f3f3f;
const ll LINF = 0x3f3f3f3f3f3f3f3f;

struct dsu {
	vector<int> e;
	dsu(int n) : e(n, -1) {}

	int find(int v) { return e[v] < 0 ? v : e[v] = find(e[v]); }
	bool same(int a, int b) { return find(a) == find(b); }
	void une(int a, int b) {
		a = find(a), b = find(b);
		if (a == b) return;
		if (e[a] < e[b]) swap(a, b);
		e[b] += e[a];
		e[a] = b;
	}
};

int construct(vector<vector<int>> p) {
	int n = sz(p);

	vector ans(n, vector<int>(n));

	auto merge1 = [&](vector<int> v) -> void {
		for (int i = 0; i < sz(v) - 1; i++) {
			int a = v[i];
			int b = v[i + 1];
			if (a == b) continue;
			ans[a][b] = 1;
			ans[b][a] = 1;
		}
	};
	auto merge2 = [&](vector<int> v) -> void {
		for (int i = 0; i < sz(v); i++) {
			int a = v[i];
			int b = v[(i + 1) % (sz(v))];
			if (a == b) continue;
			ans[a][b] = 1;
			ans[b][a] = 1;
		}
	};

	dsu dsu1(n);
	for (int i = 0; i < n; i++)
		for (int j = i; j < n; j++)
			if (p[i][j] == 1)
				dsu1.une(i, j);

	vector<vector<int>> comp1(n);
	for (int i = 0; i < n; i++) {
		int p = dsu1.find(i);
		comp1[p].push_back(i);
	}

	for (int i = 0; i < n; i++)
		merge1(comp1[i]);

	dsu dsu2(n);
	for (int i = 0; i < n; i++)
		for (int j = i; j < n; j++)
			if (p[i][j] == 2) {
				int a = dsu1.find(i);
				int b = dsu1.find(j);
				dsu2.une(a, b);
			}

	vector<vector<int>> comp2(n);
	for (int i = 0; i < n; i++) {
		int p = dsu2.find(i);
		comp2[p].push_back(i);
	}

	for (int i = 0; i < n; i++)
		merge2(comp2[i]);

	for (int i = 0; i < n; i++)
		for (int j = i + 1; j < n; j++) {
			if (!(p[i][j] == 1 && dsu1.same(i, j))) return 0;
			int a = dsu1.find(i);
			int b = dsu1.find(j);
			// if (!(p[i][j] == 2 && dsu2.same(a, b))) return 0;
		}

	build(ans);
	return 1;
}

• Subtask 1: 11 / 11
• Subtask 2: 0 / 10
• Subtask 3: 0 / 19
• Subtask 4: 0 / 35
• Subtask 5: 0 / 21
• Subtask 6: 0 / 4