Submission #1295880

#	Time	Username	Problem	Language	Result	Execution time	Memory
1295880		kawhiet	Connecting Supertrees (IOI20_supertrees)	C++20	11 / 100	120 ms	26420 KiB

supertrees

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

vector<int> cur;
map<int, int> m;

void dfs(int u, vector<vector<int>> &g, vector<bool> &vis) {
    cur.push_back(m[u]);
    vis[m[u]] = 1;
    for (auto v : g[m[u]]) {
        if (!vis[m[v]]) {
            dfs(m[v], g, vis);
        }
    }
}

// void dfs(int r, int u, vector<vector<int>> &g, vector<vector<int>> &cnt) {
//     for (auto v : g[u]) {

//     }
// }

int construct(vector<vector<int>> p) {
    int n = p.size();
    vector<vector<int>> twos(n), ones(n);
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if (p[i][j] == 2) {
                twos[i].push_back(j);
            } else if (p[i][j] == 1) {
                ones[i].push_back(j);
            } else {
                return 0;
            }
        }
    }
    for (int i = 0; i < n; i++) {
        m[i] = i;
    }
    vector<bool> vis1(n), vis2(n);
    vector<vector<int>> a, b;
    for (int i = 0; i < n; i++) {
        if (!vis1[i]) {
            cur.clear();
            dfs(i, ones, vis1);
            a.push_back(cur);
        }
    }
    vector<vector<int>> ans(n, vector<int>(n));
    for (auto k : a) {
        for (int i = 1; i < k.size(); i++) {
            m[k[i]] = k[0];
            ans[k[i]][k[i - 1]] = 1;
            ans[k[i - 1]][k[i]] = 1;
        }
    }
    for (int i = 0; i < n; i++) {
        if (!vis2[m[i]]) {
            cur.clear();
            dfs(m[i], twos, vis2);
            b.push_back(cur);
        }
    }
    for (auto k : b) {
        if (k.size() == 1) {
            continue;
        }
        if (k.size() == 2) {
            return 0;
        }
        for (int i = 1; i < k.size(); i++) {
            int u = m[k[i]], v = m[k[i - 1]];
            ans[u][v] = ans[v][u] = 1;
        }
        int u = m[k.back()], v = m[k[0]];
        ans[u][v] = ans[v][u] = 1;
    }
    for (auto k : a) {
        for (auto x : k) {
            for (auto y : k) {
                if (p[x][y] == 0) {
                    return 0;
                }
            }
        }
    }
    for (auto k : b) {
        for (auto x : k) {
            for (auto y : k) {
                if (p[x][y] == 0) {
                    return 0;
                }
            }
        }
    }
    // vector<vector<int>> g(n);
    // for (int i = 0; i < n; i++) {
    //     for (int j = 0; j < n; j++) {
    //         if (ans[i][j] == 1) {
    //             g[i].push_back(j);
    //         }
    //     }
    // }
    // vector<vector<int>> cnt(n, vector<int>(n));
    // if (cnt != p) {
        // return 0;
    // } else {
        build(ans);
        return 1;
    // }
}

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