Submission #315575

#	Time	Username	Problem	Language	Result	Execution time	Memory
315575		tigicha	Connecting Supertrees (IOI20_supertrees)	C++14	19 / 100	1088 ms	30220 KiB

supertrees

#include "supertrees.h"
#include<bits/stdc++.h>
using namespace std;
int par[1005], ar[1005], a[1005][1005], ans[1005][1005], fix1[1005], n, fix[1005];
vector<int>vec1[1005], vec[1005], v1;
vector<vector<int> >answer;
int parent(int x){
	if(par[x]==x) return x;
	return par[x]=parent(par[x]);
}
void dsu(int x, int y){
	x=parent(x);
	y=parent(y);
	if(x==y) return;
	if(ar[x]<ar[y]) swap(x, y);
	par[y]=x;
	ar[x]+=ar[y];
}
void rec(int z){
	for(int i=0; i<vec1[z].size(); i++)
	for(int j=i+1; j<vec1[z].size(); j++){
		int x=vec1[z][i];
		int y=vec1[z][j];
		if(a[x][y]==1){
			 vec[x].push_back(y);
			 vec[y].push_back(x);
		}
	}
	v1.clear();
	for(int i=0; i<vec1[z].size(); i++){
		int x=vec1[z][i]; 
		if(fix[x]) continue;
		v1.push_back(x);
		fix1[x]=1;
		if(!fix[x])
		for(int j=0; j<vec[x].size(); i++){
			fix[vec[x][j]]=x;
			ans[x][vec[x][j]]=1;
			ans[vec[x][j]][x]=1;
		}
	}
	if(v1.size()>1)
	for(int i=0; i<v1.size(); i++){
		ans[v1[i]][v1[(i+1)%v1.size()]]=1;
		ans[v1[(i+1)%v1.size()]][v1[i]]=1;
	}
}
bool check(){
	for(int i=1; i<=n; i++){
		std::vector<int> v2;
		for(int j=1; j<=n; j++){
			if(i==j) ans[i][i]=0;
			else{
				if(a[i][j]==0 && parent(i)==parent(j)) return 0;
				if(!fix1[i] && !fix1[j] && a[i][j]==2 && fix[i]==fix[j]) return 0;
			}
			v2.push_back(ans[i][j]); 
		}
		answer.push_back(v2);
	}
	return 1;
}
int construct(std::vector<std::vector<int> > v){
	n=v.size(); 
	for(int i=1; i<=n; i++){
		par[i]=i;
		ar[i]=1;
	}
	for(int i=1; i<=n; i++)
	for(int j=1; j<=n; j++){
		a[i][j]=v[i-1][j-1];
		if(a[i][j]==3) return 0;	
		if(a[i][j]!=0) dsu(i, j);
	}
	for(int i=1; i<=n; i++)
	vec1[parent(i)].push_back(i);
	for(int i=1; i<=n; i++){
		rec(i);
		if(v1.size()==2 && a[v1[0]][v1[1]]==2) return 0;
	}
	if(!check()) return 0;
	build(answer);
	return 1;
}

Compilation message (stderr)

supertrees.cpp: In function 'void rec(int)':
supertrees.cpp:20:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   20 |  for(int i=0; i<vec1[z].size(); i++)
      |               ~^~~~~~~~~~~~~~~
supertrees.cpp:21:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   21 |  for(int j=i+1; j<vec1[z].size(); j++){
      |                 ~^~~~~~~~~~~~~~~
supertrees.cpp:30:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |  for(int i=0; i<vec1[z].size(); i++){
      |               ~^~~~~~~~~~~~~~~
supertrees.cpp:36:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |   for(int j=0; j<vec[x].size(); i++){
      |                ~^~~~~~~~~~~~~~
supertrees.cpp:43:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |  for(int i=0; i<v1.size(); i++){
      |               ~^~~~~~~~~~

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