Submission #798160

#	Time	Username	Problem	Language	Result	Execution time	Memory
798160		nnin	Connecting Supertrees (IOI20_supertrees)	C++14	100 / 100	168 ms	22100 KiB

supertrees

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

int dsu[1001];
int par(int x) {
    if(dsu[x]==x) return x;
    return dsu[x] = par(dsu[x]);
}

int dsu2[1001];
int par2(int x) {
    if(dsu2[x]==x) return x;
    return dsu2[x] = par2(dsu2[x]);
}

vector<int> cyc[1001];

int construct(std::vector<std::vector<int>> p) {
	int n = p.size();
	vector<vector<int>> answer(n, vector<int>(n, 0));

	for(int i=0;i<n;i++) dsu[i] = dsu2[i] = i;

	for(int i=0;i<n;i++) for(int j=i+1;j<n;j++) {

        if(p[i][j]==3) return 0;

        if(p[i][j]==1) {
            int pari = par(i);
            int parj = par(j);
            if(pari!=parj) {
                dsu[pari] = parj;
                answer[pari][parj] = answer[parj][pari] = 1;
            }
        }
	}

	for(int i=0;i<n;i++) for(int j=i+1;j<n;j++) {
        if(p[i][j]==2) {
            int pari = par2(par(i));
            int parj = par2(par(j));
            if(pari!=parj) {
                dsu2[pari] = parj;
            }
        }
	}
	for(int i=0;i<n;i++) {
        if(par(i)==i) cyc[par2(i)].push_back(i);
	}
	for(int i=0;i<n;i++) {
        if(cyc[i].size()<=1) continue;
        if(cyc[i].size()==2) return 0;
        int last = cyc[i][cyc[i].size()-1];
        for(int cur:cyc[i]) {
            answer[last][cur] = answer[cur][last] = 1;
            last = cur;
        }
	}

	for(int i=0;i<n;i++) for(int j=0;j<n;j++) {
        if(!p[i][j]) {
            int pari = par(i);
            int parj = par(j);
            if(pari==parj || par2(pari)==par2(parj)) {
                return 0;
            }
        }
	}

	build(answer);
	return 1;
}
/*
4
1 1 2 2
1 1 2 2
2 2 1 2
2 2 2 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