Submission #599917

#	Time	Username	Problem	Language	Result	Execution time	Memory
599917		Jomnoi	Magic Tree (CEOI19_magictree)	C++17	3 / 100	60 ms	11820 KiB

magictree

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

const int MAX_N = 1e5 + 5;
const int MAX_K = 1e5 + 5;

vector <pair <int, int>> riped[MAX_K];
vector <int> graph[MAX_N];
int parent[MAX_N];
int depth[MAX_N];
bool dead[MAX_N];
pair <int, int> fruit[MAX_N];
long long sum;

void dfs(int u) {
    for(auto v : graph[u]) {
        depth[v] = depth[u] + 1;
        dfs(v);
    }
}

void dfs2(int u, int k) {
    if(dead[u] == true) {
        return;
    }

    if(fruit[u].first == k) {
        sum += fruit[u].second;
    }
    dead[u] = true;

    for(auto v : graph[u]) {
        dfs2(v, k);
    }
}

int main() {
    cin.tie(nullptr)->sync_with_stdio(false);

    int N, M, K;
    cin >> N >> M >> K;

    for(int i = 2; i <= N; i++) {
        cin >> parent[i];

        graph[parent[i]].push_back(i);
    }

    dfs(1);

    long long ans = 0;
    bool sub2 = true;
    for(int i = 1; i <= M; i++) {
        int v, d, w;
        cin >> v >> d >> w;

        riped[d].emplace_back(v, w);
        fruit[v] = make_pair(d, w);

        if(graph[v].size() > 0) {
            sub2 = false;
        }
        ans += w;
    }

    if(sub2 == true) {
        cout << ans;
        return 0;
    }

    ans = 0;
    for(int i = 1; i <= K; i++) {
        sort(riped[i].begin(), riped[i].end(), [&](const pair <int, int> &a, const pair <int, int> &b) {
            return depth[a.first] > depth[b.first];
        });
    }
    
    for(int mask = 0; mask < (1<<K); mask++) {
        sum = 0;
        for(int i = 1; i <= N; i++) {
            dead[i] = false;
        }
        for(int k = 0; k < K; k++) {    
            if(mask & (1<<k)) {
                for(auto [v, w] : riped[k + 1]) {
                    dfs2(v, k + 1);
                }
            }
        }
        ans = max(ans, sum);
    }
    cout << ans;
    return 0;
}

• Subtask 1: 0 / 6
• Subtask 2: 3 / 3
• Subtask 3: 0 / 11
• Subtask 4: 0 / 12
• Subtask 5: 0 / 16
• Subtask 6: 0 / 13
• Subtask 7: 0 / 22
• Subtask 8: 0 / 17