Submission #1058496

#	Time	Username	Problem	Language	Result	Execution time	Memory
1058496		TheQuantiX	Beech Tree (IOI23_beechtree)	C++17	17 / 100	83 ms	30452 KiB

beechtree

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

using namespace std;
using ll = long long;

ll n, m, q, k, x, y, a, b, l;
vector<ll> G[200000];
vector<int> p, c;

bool check(vector<int> &v) {
    map<ll, ll> mp;
    vector<ll> v1(n);
    for (int i = 1; i < v.size(); i++) {
        v1[i] = mp[c[v[i]]];
        mp[c[v[i]]]++;
        // cout << p[v[i]] << ' ' << v1[i] << ' ' << v[v1[i]] << '\n';
        if (p[v[i]] != v[v1[i]]) {
            return 0;
        }
    }
    return 1;
}

bool comp(vector<int> &v, vector<int> &u) {
    return v.size() < u.size();
}

bool check2vec(vector<int> &v, vector<int> &u) {
    // for (auto i : v) {
    //     cout << i << ' ';
    // }
    // cout << '\n';
    // for (auto i : u) {
    //     cout << i << ' ';
    // }
    // cout << '\n';
    multiset<ll> st;
    for (int i : u) {
        st.insert(i);
    }
    for (int i : v) {
        if (!st.count(i)) {
            return 0;
        }
        st.erase(st.find(i));
    }
    return 1;
}

vector<int> beechtree(int N, int M, vector<int> P, vector<int> C) {
    n = N;
    m = M;
    p = P;
    c = C;
    bool testcase2 = 0;
    bool testcase3 = 0;
    for (int i = 1; i < n; i++) {
        G[P[i]].push_back(i);
        if (P[i] != i - 1) {
            testcase2 = 0;
        }
        if (i != 0 && P[i] != 0 && P[P[i]] != 0) {
            testcase3 = 0;
        }
    }
    if (n <= 8) {
        vector<int> ans(n);
        vector< vector<int> > has(n);
        for (int i = n - 1; i >= 0; i--) {
            // cout << i << '\n';
            has[i].push_back(i);
            for (int j : G[i]) {
                for (int k : has[j]) {
                    has[i].push_back(k);
                }
            }
            sort(has[i].begin(), has[i].end());
            bool fl = 0;
            do {
                // cout << has[i].size() << endl;
                if (has[i][0] != i) {
                    break;
                }
                fl |= check(has[i]);
                if (fl) {
                    break;
                }
            } while (next_permutation(has[i].begin(), has[i].end()));
            ans[i] = fl;
        }
        return ans;
    }
    if (testcase2) {
        vector<int> ans(n);
        ans[n - 1] = 1;
        ans[n - 2] = 1;
        for (int i = n - 3; i >= 0; i--) {
            ans[i] = (ans[i + 1] & (c[i + 1] == c[i + 2]));
        }
        return ans;
    }
    if (testcase3) {
        vector<int> ans(n);
        for (int i = n - 1; i >= 0; i--) {
            ans[i] = 1;
            set<ll> st;
            for (auto j : G[i]) {
                ans[i] &= ans[j];
                st.insert(c[j]);
            }
            if (st.size() != G[i].size()) {
                ans[i] = 0;
                continue;
            }
            if (i == 0) {
                vector< vector<int> > vec(1);
                for (int j : G[i]) {
                    vec[0].push_back(c[j]);
                }
                for (int j : G[i]) {
                    vec.resize(vec.size() + 1);
                    for (int k : G[j]) {
                        vec[vec.size() - 1].push_back(c[k]);
                    }
                    ans[i] &= check2vec(vec[vec.size() - 1], vec[0]);
                }
                // for (auto &j : vec) {
                //     sort(j.begin(), j.end());
                // }
                sort(vec.begin(), vec.end(), comp);
                for (int j = 0; j < vec.size() - 1; j++) {
                    ans[i] &= check2vec(vec[j], vec[j + 1]);
                }
            }
        }
        return ans;
    }
    vector<int> ans(n);
    vector< unordered_set<int> > has(n);
    for (int i = n - 1; i >= 0; i--) {
        ans[i] = 1;
        set<ll> st1;
        for (auto j : G[i]) {
            ans[i] &= ans[j];
            st1.insert(c[j]);
        }
        if (st1.size() != G[i].size()) {
            ans[i] = 0;
            continue;
        }
        // cout << i << '\n';
        for (int j : G[i]) {
            if (has[j].size() > has[i].size()) {
                swap(has[j], has[i]);
            }
            if (has[j].size() > 0 && has[i].size() > 0) {
                ans[i] = 0;
            }
            for (int k : has[j]) {
                if (has[i].count(k)) {
                    ans[i] = 0;
                }
                has[i].insert(k);
            }
        }
        unordered_set<int> st;
        for (int j : G[i]) {
            if (has[i].count(c[j])) {
                has[i].erase(c[j]);
            }
            else {
                st.insert(c[j]);
            }
        }
        if (!has[i].empty()) {
            ans[i] = 0;
        }
        has[i] = st;
    }
    return ans;
}

Compilation message (stderr)

beechtree.cpp: In function 'bool check(std::vector<int>&)':
beechtree.cpp:14:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |     for (int i = 1; i < v.size(); i++) {
      |                     ~~^~~~~~~~~~
beechtree.cpp: In function 'std::vector<int> beechtree(int, int, std::vector<int>, std::vector<int>)':
beechtree.cpp:132:35: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  132 |                 for (int j = 0; j < vec.size() - 1; j++) {
      |                                 ~~^~~~~~~~~~~~~~~~

• Subtask 0: 0 / 0
• Subtask 1: 9 / 9
• Subtask 2: 0 / 5
• Subtask 3: 0 / 9
• Subtask 4: 8 / 8
• Subtask 5: 0 / 14
• Subtask 6: 0 / 14
• Subtask 7: 0 / 12
• Subtask 8: 0 / 17
• Subtask 9: 0 / 12