Submission #300293

#	Time	Username	Problem	Language	Result	Execution time	Memory
300293		aljasdlas	Connecting Supertrees (IOI20_supertrees)	C++14	100 / 100	254 ms	26360 KiB

supertrees

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

bool possible = true;
vector<vector<int>> b;
int n;
bitset<1005> vis;
bitset<1005> onevis;
bitset<1005> isOne;

vector<vector<int>> components;
int compNum[1005];
vector<vector<int>> onecomponents;
int onecompNum[1005];
vector<vector<int>> p;

void dfs(int u) {
// << u << " ";
	vis[u] = 1;
	compNum[u] = components.size();
	components.back().push_back(u);
	for(int v = 0; v < n; v++)
		if(!vis[v] && p[u][v])
			dfs(v);
}



void onedfs(int u) {
	onevis[u] = 1;
	onecompNum[u] = onecomponents.size();
	onecomponents.back().push_back(u);
	for(int v = 0; v < n; v++)
		if(!onevis[v] && p[u][v] == 1)
			onedfs(v);
}


int construct(vector<vector<int>> p_) {
	p = p_;
	n = p.size();

	for (int i = 0; i < n; i++) {
		vector<int> row;
		row.resize(n);
		b.push_back(row);
	}

	vis.reset();

	for(int i = 0; i < n; i++) {
		if(!vis[i]) {
			components.push_back(vector<int>(0));
		// << "Comp " << components.size() << ": ";
			dfs(i);
		// << endl;
		}
	}
	for(int i = 0; i < n; i++) {
		if(!onevis[i]) {
			onecomponents.push_back(vector<int>(0));
		// << "Comp " << components.size() << ": ";
			onedfs(i);
		// << endl;
			if(onecomponents.back().size() == 1) {
				onecompNum[i] = 0;
				onecomponents.pop_back();
			}
		}
	}


	for(int i = 0; i < n; i++)
		for(int j = 0; j < n; j++) {
			if(p[i][j] == 3) return 0;
			if(compNum[i] == compNum[j] && p[i][j] == 0)
				return 0;
			else if(compNum[i] != compNum[j] && p[i][j] > 0)
				return 0;
			if(onecompNum[i] == onecompNum[j] && onecompNum[i] != 0 && p[i][i] != 1)
				return 0;
		}

	for(auto &v: components) {
		isOne.reset();
		if(v.size() == 1)
			continue;


		vector<int> is[3];
		for(auto &x: v)
			if(onecompNum[x] == 0) is[2].push_back(x);

		for(auto &x: v) {
			if(onecompNum[x] > 0) {
				auto &w = onecomponents[onecompNum[x]-1];
				for(int i = 0; i+1 < w.size(); i++) {
					b[w[i]][w[i+1]] = 1;
					b[w[i+1]][w[i]] = 1;
				}
				is[2].push_back(w.back());
				for(auto y: w)
					onecompNum[y] = -1;
			}
		}
		
		
	// << "Is 1: "; for(auto x: is[1]) cerr << x << " "; cerr << endl;
	// << "Is 2: "; for(auto x: is[2]) cerr << x << " "; cerr << endl;

		if(is[2].size() == 2) return 0;

		if(is[2].size() > 2) {
			for(int i = 1; i < is[2].size(); i++) {
				b[is[2][i-1]][is[2][i]] = 1;
				b[is[2][i]][is[2][i-1]] = 1;
			}
			b[is[2][is[2].size()-1]][is[2][0]] = 1;
			b[is[2][0]][is[2][is[2].size()-1]] = 1;
		}
	}

	if(!possible)
		return 0;
	
	build(b);
	return 1;
}

Compilation message (stderr)

supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:98:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   98 |     for(int i = 0; i+1 < w.size(); i++) {
      |                    ~~~~^~~~~~~~~~
supertrees.cpp:115:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  115 |    for(int i = 1; i < is[2].size(); i++) {
      |                   ~~^~~~~~~~~~~~~~

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