Submission #789670

#	Time	Username	Problem	Language	Result	Execution time	Memory
789670		FEDIKUS	Connecting Supertrees (IOI20_supertrees)	C++17	100 / 100	153 ms	24056 KiB

supertrees

#include "supertrees.h"
#include <vector>
#include<map>
#include<algorithm>

using namespace std;

const int maxn=1010;

int dsu[maxn];
int dsu2[maxn];

int cale(int a,int *dsu){
	return dsu[a]==a ? a:cale(dsu[a],dsu);
}
void join(int a,int b,int *dsu){
	dsu[cale(a,dsu)]=cale(b,dsu);
}

int construct(vector<vector<int>> p) {
	int n = p.size();
	vector<vector<int>> answer;
	for (int i = 0; i < n; i++) {
		vector<int> row;
		row.resize(n);
		answer.push_back(row);
	}

	for(int i=0;i<n;i++) dsu[i]=i;
	for(int i=0;i<n;i++) dsu2[i]=i;
	for(int i=0;i<n;i++){
		for(int j=0;j<i;j++){
			if(p[i][j]==1) join(i,j,dsu);
			if(p[i][j]==3) return 0;
		}
	}
	for(int i=0;i<n;i++){
		if(i!=cale(i,dsu)){
			answer[i][cale(i,dsu)]=1;
			answer[cale(i,dsu)][i]=1;
		}
	}
	for(int i=0;i<n;i++){
		for(int j=0;j<i;j++){
			if(p[i][j]==0) if(cale(i,dsu)==cale(j,dsu)) return 0;
			if(p[i][j]==2){
				if(cale(i,dsu)==cale(j,dsu)) return 0;
				join(cale(i,dsu),cale(j,dsu),dsu2);
			}
		}
	}
	for(int i=0;i<n;i++){
		for(int j=0;j<i;j++){
			if(p[i][j]==0) if(cale(cale(i,dsu),dsu2)==cale(cale(j,dsu),dsu2)) return 0;
		}
	}
	map<int,vector<int> > kurac;
	for(int i=0;i<n;i++){
		kurac[cale(cale(i,dsu),dsu2)].push_back(cale(i,dsu));
	}
	for(auto i:kurac){
		sort(i.second.begin(),i.second.end());
		i.second.resize(unique(i.second.begin(),i.second.end())-i.second.begin());
		int prev=i.second.back();
		if(i.second.size()==2) return 0;
		for(int j:i.second){
			if(prev==j) break;
			if(prev!=-1){
				answer[prev][j]=1;
				answer[j][prev]=1;
			}
			prev=j;
		}
	}
	build(answer);
	return 1;
}

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