Submission #1198474

#	Time	Username	Problem	Language	Result	Execution time	Memory
1198474		PlayVoltz	Connecting Supertrees (IOI20_supertrees)	C++20	100 / 100	132 ms	22212 KiB

supertrees

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

#define pii pair<int, int>
#define mp make_pair
#define pb push_back
#define fi first
#define se second

vector<int> dsu;

int fp(int a){
	if (dsu[a]==-1)return a;
	return dsu[a]=fp(dsu[a]);
}

void merge(int a, int b){
	a=fp(a), b=fp(b);
	if (a==b)return;
	dsu[a]=b;
}

int construct(vector<vector<int>> p){
	int n=p.size();
	vector<vector<int> > ans(n, vector<int>(n, 0)), temp(n);
	for (int i=0; i<n; ++i)for (int j=0; j<n; ++j)if (p[i][j]==3)return 0;
	dsu.assign(n, -1);
	for (int i=0; i<n; ++i)for (int j=0; j<n; ++j)if (p[i][j])merge(i, j);
	for (int i=0; i<n; ++i)for (int j=0; j<n; ++j)if (fp(i)==fp(j)&&!p[i][j])return 0;
	dsu.assign(n, -1);
	for (int i=0; i<n; ++i)for (int j=0; j<n; ++j)if (p[i][j]==1)merge(i, j);
	for (int i=0; i<n; ++i)for (int j=0; j<n; ++j)if (fp(i)==fp(j)&&p[i][j]!=1)return 0;
	for (int i=0; i<n; ++i)if (i!=fp(i))ans[i][fp(i)]=ans[fp(i)][i]=1;
	vector<int> par;
	for (int i=0; i<n; ++i)if (dsu[i]==-1)par.pb(i);
	dsu.assign(n, -1);
	for (auto i:par)for (auto j:par)if (p[i][j]==2)merge(i, j);
	for (int i=0; i<n; ++i)temp[fp(i)].pb(i);
	for (auto a:temp)if (a.size()==2)return 0;
	for (auto a:temp)if (a.size()!=1)for (int i=0; i<a.size(); ++i)ans[a[i]][a[(i+1)%a.size()]]=ans[a[(i+1)%a.size()]][a[i]]=1;
	build(ans);
	return 1;
}

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