Submission #300343

#	Time	Username	Problem	Language	Result	Execution time	Memory
300343		fpc_coder	Connecting Supertrees (IOI20_supertrees)	C++17	40 / 100	257 ms	22264 KiB

supertrees

#include <bits/stdc++.h>
#include "supertrees.h"

using namespace std;

int construct(vector<vector<int>> p) {
    vector<vector<int>> b(p.size(), vector<int>(p.size(), 0));
    int n = (int) p.size();
    vector<int> par(n, -1);
    vector<bool> vis(n, false);
    bool subtask3 = false;
    for (int i = 0; i < n; i++) {
        if (*max_element(p[i].begin(), p[i].end()) == 2) {
            subtask3 = true;
            break;
        }
    }
    if (!subtask3) {
        for (int i = 0; i < n; i++) {
            if (vis[i]) continue;
            par[i] = i;
            for (int j = 0; j < n; j++) {
                if (i == j) continue;
                if (p[i][j]) {
                    if (vis[j]) return 0;
                    vis[j] = true;
                    b[i][j] = b[j][i] = 1;
                    par[j] = i;
                }
            }
        }
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                if (i == j) continue;
                if (par[i] == par[j] && p[i][j] == 0) return 0;
                if (par[i] != par[j] && p[i][j] == 1) return 0;
            }
        }
        build(b);
        return 1;
    }
    else {
        for (int i = 0; i < n; i++) {
            vector<int> v;
            if (!vis[i]) {
                for (int j = 0; j < n; j++) {
                    if (p[i][j] == 2) {
                        v.push_back(j);
                        vis[i] = true; vis[j] = true;
                    }
                }
                if ((int) v.size() == 1) return 0;
                if ((int) v.size() >= 2) {
                    for (int j = 0; j + 1 < (int) v.size(); j++) {
                        b[v[j]][v[j + 1]] = 1;
                        b[v[j + 1]][v[j]] = 1;
                    }
                    b[v[0]][i] = 1;
                    b[i][v[0]] = 1;
                    b[v[(int) v.size() - 1]][i] = 1;
                    b[i][v[(int) v.size() - 1]] = 1;
                }
            }
        }
        for (int i = 0; i < n; i++) par[i] = i;
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < i; j++) {
                if (p[i][j] == 2) par[j] = i;
            }
        }
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                if (par[i] == par[j] && p[i][j] == 0) return 0;
                if (par[i] != par[j] && p[i][j] == 2) return 0;
            }
        }
        build(b);
        return 1;
    }
}

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