Submission #838261

#	Time	Username	Problem	Language	Result	Execution time	Memory
838261		caganyanmaz	Connecting Supertrees (IOI20_supertrees)	C++17	100 / 100	183 ms	24096 KiB

supertrees

#include <bits/stdc++.h>
#include "supertrees.h"
//#define DEBUGGING
#ifdef DEBUGGING
#include "../debug.h"
#else
#define debug(x...) void(42)
#endif
using namespace std;
constexpr static int MXN = 1e3 + 5;
struct Node
{
	int head, tail, size, nxt;
	Node(int i) : head(i), tail(i), size(1), nxt(-1) {}
	Node() : Node(-1) {}
};
Node node[MXN];
Node supernode[MXN];

void merge(int a, int b, Node arr[MXN]);
int construct(vector<vector<int>> p)
{
	int n = p.size();
	vector<vector<int>> answer(n, vector<int>(n));
	for (int i = 0; i < n; i++) 
		node[i] = Node(i);
	for (int i = 0; i < n; i++)
		for (int j = i+1; j < n; j++)
			if (p[i][j] == 3)
				return 0;
	for (int i = 0; i < n; i++)
	{
		for (int j = i+1; j < n; j++)
		{
			if (p[i][j] == 1 && node[i].head != node[j].head)
			{
				merge(node[i].head, node[j].head, node);
				answer[i][j] = answer[j][i] = 1;
			}
		}
	}
	for (int i = 0; i < n; i++)
		supernode[i] = Node(i);
	for (int i = 0; i < n; i++)
		for (int j = i+1; j < n; j++)
			if (p[i][j] == 2 && supernode[node[i].head].head != supernode[node[j].head].head)
				merge(supernode[node[i].head].head, supernode[node[j].head].head, supernode);
	for (int i = 0; i < n; i++)
		for (int j = i+1; j < n; j++)
			if ((p[i][j] == 0 && supernode[node[i].head].head == supernode[node[j].head].head) || (p[i][j] == 1 && node[i].head != node[j].head) || (p[i][j] == 2 && (node[i].head == node[j].head || supernode[node[i].head].head != supernode[node[j].head].head)))
				return 0;
	for (int i = 0; i < n; i++)
	{
		if (i != node[i].head || i != supernode[i].head || supernode[i].size == 1)
			continue;
		if (supernode[i].size == 2)
			return 0;
		for (int j = i; supernode[j].nxt != -1; j = supernode[j].nxt)
			answer[j][supernode[j].nxt] = answer[supernode[j].nxt][j] = 1;
		answer[i][supernode[i].tail] = answer[supernode[i].tail][i] = 1;
	}
	build(answer);
	return 1;
}
void merge(int a, int b, Node arr[MXN])
{
	if (arr[a].size < arr[b].size) swap(a, b);
	arr[a].size += arr[b].size;
	arr[arr[a].tail].nxt = b;
	arr[a].tail = arr[b].tail;
	for (;b!=-1;b=arr[b].nxt)
		arr[b].head = a;
}

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