Submission #1013205

#	Time	Username	Problem	Language	Result	Execution time	Memory
1013205		Luvidi	Connecting Supertrees (IOI20_supertrees)	C++17	40 / 100	170 ms	24400 KiB

supertrees

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

int par[1000],sz[1000];
vector<vector<int>> ans;

int rep(int x){
	while(x!=par[x])x=par[x];
	return x;
}

void join(int x,int y){
	x=rep(x);y=rep(y);
	if(x==y)return;
	if(sz[x]>sz[y])swap(x,y);
	par[x]=y;
	sz[y]+=sz[x];
}

void edge(int x,int y){
	ans[x][y]=1;
	ans[y][x]=1;
}

int construct(std::vector<std::vector<int>> p) {
	int n = p.size();
	for(int i=0;i<n;i++){
		par[i]=i;
		sz[i]=1;
	}
	for (int i=0;i<n;i++){
		vector<int> row;
		row.resize(n);
		ans.push_back(row);
	}
	bool s2=1,s3=1;
	for(int i=0;i<n;i++){
		for(int j=0;j<i;j++){
			if(p[i][j]){
				s2&=p[i][j]==1;
				s3&=p[i][j]==2;
				join(i,j);
			}
		}
	}
	for(int i=0;i<n;i++){
		for(int j=0;j<i;j++){
			if(p[i][j]==0){
				if(rep(i)==rep(j))return 0;
			}else{
				if(rep(i)!=rep(j))return 0;
			}
		}
	}
	vector<int> v[n];
	for(int i=0;i<n;i++)v[rep(i)].push_back(i);
	for(int i=0;i<n;i++)if(v[i].size()>1){
		if(s2){
			for(int j=0;j+1<v[i].size();j++){
				edge(v[i][j],v[i][j+1]);
			}
		}else{
			if(v[i].size()==2)return 0;
			for(int j=0;j+1<v[i].size();j++){
				edge(v[i][j],v[i][j+1]);
			}
			edge(v[i][0],v[i].back());
		}
	}
	build(ans);
	return 1;
}

Compilation message (stderr)

supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:60:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   60 |    for(int j=0;j+1<v[i].size();j++){
      |                ~~~^~~~~~~~~~~~
supertrees.cpp:65:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   65 |    for(int j=0;j+1<v[i].size();j++){
      |                ~~~^~~~~~~~~~~~

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