Submission #470418

#	Time	Username	Problem	Language	Result	Execution time	Memory
470418		jazzup	Connecting Supertrees (IOI20_supertrees)	C++14	21 / 100	297 ms	22212 KiB

supertrees

#include "supertrees.h"
#include <vector>
#include <cstdio>

using namespace std;

int par[1010];
vector<int> heads;

int findPar(int n){
	if(par[n]==n)return n;

	return par[n]=findPar(par[n]);
}

bool c[1010];
vector<vector<int> > answer;

int construct(vector<vector<int> > p) {
	int n = p.size();
	for(int i=0;i<=n;i++){
		par[i]=i;
	}
	
	

	for(int i=0;i<n;i++){
		vector<int> vv;
		answer.push_back(vv);
		for(int j=0;j<n;j++){
			answer[i].push_back(0);
		}
	}

	for(int i=0;i<n-1;i++){
		for(int j=i+1;j<n;j++){
			if(p[i][j]!=p[j][i])return 0;
		}
	}
	
	for(int i=0;i<n-1;i++){
		for(int j=i+1;j<n;j++){
			if(p[i][j]==3)return 0;

			if(p[i][j]==1){
				if(findPar(i)<findPar(j)){
					par[j]=findPar(i);
					answer[j][par[j]]=1;
					answer[par[j]][j]=1;
				}
				else if(findPar(i)>findPar(j)){
					par[i]=findPar(j);
					answer[i][par[i]]=1;
					answer[par[i]][i]=1;
				}
			}
		}
	}

	for(int i=0;i<n-1;i++){
		for(int j=i+1;j<n;j++){
			// if(i==j)continue;
			if(p[i][j]==2){
				if(findPar(i)==findPar(j)){
					return 0;
				}

				c[findPar(i)]=true;
				c[findPar(j)]=true;
			}

			else if(p[i][j]==0){
				if(findPar(i)==findPar(j)){
					return 0;
				}
			}
		}
	}

	for(int i=0;i<n;i++){
		if(c[i])heads.push_back(i);
	}

	if(!heads.empty()){
		for(int i=0;i<heads.size()-1;i++){
			answer[heads[i]][heads[i+1]]=1;
			answer[heads[i+1]][heads[i]]=1;
		}
	
		answer[heads[heads.size()-1]][heads[0]]=1;
		answer[heads[0]][heads[heads.size()-1]]=1;
	}

	if(heads.size()==2)return 0;

	for(int i=0;i<n;i++){
		for(int j=0;j<n;j++){
			if(i==j)continue;
			else if(p[i][j]==0){
				if(findPar(i)==findPar(j)){
					return 0;
				}
			}
		}
	}

	build(answer);
	return 1;
}

Compilation message (stderr)

supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:85:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   85 |   for(int i=0;i<heads.size()-1;i++){
      |               ~^~~~~~~~~~~~~~~

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