Submission #414113

#	Time	Username	Problem	Language	Result	Execution time	Memory
414113		Bill_00	Connecting Supertrees (IOI20_supertrees)	C++14	0 / 100	1 ms	332 KiB

supertrees

#include "supertrees.h"
#include <bits/stdc++.h>
using namespace std;
int head[1005],sz[1005];
vector<int>groups[1005],lines[1005];

int find(int node){
	return head[node]=(node==head[node]?node:find(head[node]));
}

void combine(int i,int j){
	int a=find(i);
	int b=find(j);
	if(a==b) return;
	if(sz[a]>sz[b]){
		head[b]=a;
		sz[a]+=sz[b];
	}
	else{
		head[a]=b;
		sz[b]+=sz[a];
	}
} 

int construct(vector<vector<int> >p) {
	// cout << "LOL" << '\n';
	int n = p.size();
	vector<vector<int> > ans;
	for (int i = 0; i < n; i++) {
		vector<int> row;
		row.resize(n);
		ans.push_back(row);
	}
	for(int i=0;i<n;i++){
		head[i]=i;
		sz[i]=1;
	}
	for(int i=0;i<n;i++){
		for(int j=0;j<n;j++){
			if(p[i][j]==3) return 0;
			if(p[i][j]>0){
				combine(i,j);
			}
		}
	}
	for(int i=0;i<n;i++){
		groups[find(i)].push_back(i);
	}
	for(int i=0;i<n;i++){
		head[i]=i;
		sz[i]=1;
	}
	for(int i=0;i<n;i++){
		int szz=groups[i].size();
		// cout << szz << '\n';
		for(int j=0;j<szz;j++){
			for(int k=0;k<szz;k++){
				int a=groups[i][j];
				int b=groups[i][k];
				if(p[a][b]==0) return 0;
				if(p[a][b]==1) combine(a,b);
			}
		}
		for(int j=0;j<szz;j++){
			int node=groups[i][j];
			lines[find(node)].push_back(node);
			// cout << node << ' ' << find(node) << '\n';
		}
		vector<int>cycle;
		for(int j=0;j<szz;j++){
			int node=groups[i][j];
			int szzz=lines[node].size();
			if(szzz) cycle.push_back(lines[node][0]);
			for(int k=0;k<szzz;k++){
				for(int g=0;g<szzz;g++){
					int a=lines[node][k];
					int b=lines[node][g];
					if(p[a][b]==2) return 0;
				}
			}
			for(int k=1;k<szzz;k++){
				int a=lines[node][k];
				int b=lines[node][k-1];
				ans[a][b]=1;
				ans[b][a]=1;
			}
		}
		int szzzz=cycle.size();
		if(szzzz==2) return 0;
		for(int j=0;j<szzzz;j++){
			int a=cycle[j];
			int b=cycle[(j-1+szzzz)%szzzz];
			ans[a][b]=1;
			ans[b][a]=1;
		}
	}
	build(ans);
	return 1;
}

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