Submission #899402

#	Time	Username	Problem	Language	Result	Execution time	Memory
899402		oblantis	Connecting Supertrees (IOI20_supertrees)	C++17	21 / 100	161 ms	26420 KiB

supertrees

#include "supertrees.h"
#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
#define all(v) v.begin(), v.end()
#define pb push_back
#define ss second
#define ff first
#define vt vector
using namespace std;
//using namespace __gnu_pbds;
typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef pair<double, int> pdi;
const ll inf = 1e18;
const int mod = 1e9+7;
const int maxn = 1000 + 2;
vector<int> g[maxn];
int x;
int h[maxn], oh[maxn], used[maxn];
bool two[maxn], three[maxn];
bool was[maxn];
void dfs(int v){
	h[v] = x;
	was[v] = 1;
	for(auto i : g[v]){
		if(!was[i]){
			dfs(i);
		}
	}
}
int construct(vector<vector<int>> p) {
	int n = p.size();
	vector<vector<int>> ans(n);
	for(int i = 0; i < n; i++)ans[i].resize(n);
	for(int i = 0; i < n; i++){
		for(int j = 0; j <= i; j++){
			if(i == j){
				if(p[i][i] != 1)return 0;
				continue;
			}
			if(p[i][j]){
				g[j].pb(i);
				g[i].pb(j);
			}
			if(p[i][j] != p[j][i]){
				return 0;
			}
		}
	}
	for(int i = 0; i < n; i++){
		if(!was[i]){
			x = i;
			dfs(i);
		}
	}
	for(int i = 0; i < n; i++){
		oh[i] = used[i] = -1;
		for(int j = 0; j < n; j++){
			if(h[i] == h[j] && p[i][j] == 0){
				return 0;
			}
			if(h[i] == h[j]){
				if(p[i][j] == 2){
					two[h[i]] = 1;
				}
				else if(p[i][j] == 3){
					three[h[i]] = 1;
				}
				if(two[h[i]] && three[h[i]]){
					return 0;
				}
			}
		}
	}
	vt<int> unq;
	for(int i = 0; i < n; i++){
		if(oh[i] == -1){
			unq.pb(i);
			oh[i] = i;
			for(auto j : g[i]){
				if(p[i][j] == 1){
					if(oh[j] != -1){
						return 0;
					}
					oh[j] = i;
					ans[i][j] = ans[j][i] = 1;
				}
			}
		}
	}
	int sz = unq.size();
	for(int I = 0; I < sz; I++){
		int i = unq[I];
		if(used[i] != -1)continue;
		used[i] = i;
		if(h[i] != i)return 0;
		if(!three[i] && !two[i])continue;
		bool wt = 0;
		if(three[i])wt = 1;
		int o = -1, ls = -1, z = -1;
		for(int J = 0; J < sz; J++){
			int j = unq[J];
			if(p[i][j] > 1 && used[j] == -1){
				used[j] = i;
				if(o == -1){
					o = j;
					ans[i][o] = ans[o][i] = 1;
				}
				else {
					if(ls == -1)ls = j;
					ans[z][j] = ans[j][z] = 1;
					z = j;
				}
			}
			else if(p[i][j] > 1)return 0;
		}
		if(z == -1)return 0;
		ans[o][z] = ans[z][o] = 1;
		if(wt && z == ls){
			return 0;
		}
		else if(wt){
			ans[z][i] = ans[i][z] = 1;
		}
	}
	build(ans);
	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