Submission #1148929

#	Time	Username	Problem	Language	Result	Execution time	Memory
1148929		zhasyn	Connecting Supertrees (IOI20_supertrees)	C++20	100 / 100	155 ms	26148 KiB

supertrees

#include "supertrees.h"
#include <bits/stdc++.h>
#define pb push_back
#define pf push_front
using namespace std;
#define F first
#define S second
typedef long long ll;
#define pii pair <int, int>
#define pll pair <ll, ll>
typedef long double ld;
const ll N = 1000 + 100, M = 4096 + 10, len = 21, inf = 1e18;
const ll mod = 1e9 + 7;
vector <int> q[N], g[N];
vector<vector<int>> ans;
vector <int> c, ml;
bool was[N], op[N];
void dfs1(int v){
	was[v] = true;
	c.pb(v);
	for(auto u : q[v]){
		if(was[u] == true) continue;
		dfs1(u);
	}
	for(auto u : g[v]){
		if(was[u] == true) continue;
		dfs1(u);
	}
}
void dfs2(int v){
	op[v] = true;
	ml.pb(v);
	for(auto u : g[v]){
		if(op[u]) continue;
		dfs2(u);
	}
}
// void build(vector<vector<int>> p){
	// for(auto u : p){
		// for(auto v : u){
			// cout << v << " ";
		// }
		// cout << endl;
	// }
// }
int construct(vector<vector<int>> p) {
	int n = p.size();
	bool can = true;
	for (int i = 0; i < n; i++) {
		vector<int> row;
		row.resize(n);
		ans.push_back(row);
	}
	
	// if(n <= 3){
		// build(ans);
		// return 1;
	// }
	for(int i = 0; i < n; i++){
		for(int j = 0; j < n; j++){
			if(i == j) continue;
			if(p[i][j] == 2) q[i].pb(j);
			if(p[i][j] == 1) g[i].pb(j);
			if(p[i][j] == 3) can = false;
		}
	}
	//cout << "was\n";
	for(int i = 0; i < n; i++){
		if(was[i] == false){
			dfs1(i);
			vector <int> nw;
			for(auto u : c){
				if(op[u] == false){
					dfs2(u);
					for(int j = 1; j < (int)ml.size(); j++){
						ans[ml[j]][ml[j - 1]] = ans[ml[j - 1]][ml[j]] = 1;
					}
					for(int j = 0; j < (int)ml.size(); j++){
						for(int k = 0; k < (int)ml.size(); k++){
							if(p[ml[j]][ml[k]] == 0) can = false;
						}
					}
					nw.pb(ml[0]);
					ml.clear();
				}
			}
			c.clear();
			if((int)nw.size() == 1) continue;
			if((int)nw.size() == 2){
				can = false;
				continue;
			}
			for(int j = 1; j < (int)nw.size(); j++){
				ans[nw[j]][nw[j - 1]] = ans[nw[j - 1]][nw[j]] = 1;
			}
			ans[nw[(int)nw.size() - 1]][nw[0]] = ans[nw[0]][nw[(int)nw.size() - 1]] = 1;
			
			for(int j = 0; j < (int)nw.size(); j++){
				for(int k = 0; k < (int)nw.size(); k++){
					if(p[nw[j]][nw[k]] == 0) can = false;
				}
			}
		}
	}
	if(can) build(ans);
	return can;
}

/*
int main() {
  ios::sync_with_stdio(false);
  cin.tie(NULL);
  vector<vector<int>> p;
  int n;
  cin >> n;
  for(int i = 0, x; i < n; i++){
  	vector <int >cur;
  	for(int j = 0; j < n; j++){
  		cin >> x;
  		cur.pb(x);
  	}
  	p.pb(cur);
  }
  construct(p);
  return 0;
}

*/

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