Submission #393123

#	Time	Username	Problem	Language	Result	Execution time	Memory
393123		abdzag	Connecting Supertrees (IOI20_supertrees)	C++17	21 / 100	256 ms	22164 KiB

supertrees

#include<bits/stdc++.h>
#include"supertrees.h"
#define rep(i,a,b) for(int i=a;i<int(b);i++)
#define rrep(i,a,b)for(int i=a;i>int(b);i--)
#define all(v) v.begin(),v.end()
#define trav(a,v) for(auto& a: v)
typedef long long ll;
using namespace std;
const long long inf = 1e15;

vector<ll> p(2001);
vector<ll> Rank(2001);
ll Ufindset(ll i) {
	if (p[i] == i)return i;
	return p[i] = Ufindset(p[i]);
}
void UjoinSet(ll i, ll j) {
	ll si = Ufindset(i);
	ll sj = Ufindset(j);
	if (sj == si)return;
	if ( Rank[sj]> Rank[si])swap(sj, si);
	p[sj] = si;
	if (Rank[sj] == Rank[si]) Rank[si]++;
}

int construct(vector<vector<int>> v) {
	rep(i, 0, 2001)p[i] = i;
	vector<vector<int>> b(v.size(), vector<int>(v.size()));
	rep(i, 0, v.size()) {
		ll root = p[i];
		ll last = i;
		bool two = false;
		rep(j, 0, v.size()) {
			if (v[i][j]) {
				if (v[i][j] == 2)two = true;
				if (j == i)continue;
				if (p[j]!=j)if (p[j] != root)return 0;
				if (root == i) {
					UjoinSet(last, j);
					b[last][j] = 1;
					b[j][last] = 1;
				}
				last = j;
			}
			else if (p[j] == p[i]) return 0;
		}
		if (two) {
			b[last][i] = 1;
			b[i][last]=1;
		}
	}
	build(b);
	return 1;
}

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