Submission #561560

#	Time	Username	Problem	Language	Result	Execution time	Memory
561560		piOOE	Road Closures (APIO21_roads)	C++17	0 / 100	221 ms	31872 KiB

roads

#include "roads.h"

#include <bits/stdc++.h>

using namespace std;

#define all(x) begin(x), end(x)

typedef long long ll;

const int N = 2001;
int A[N], B[N], W[N], n;
ll dp[N][N];
vector <pair<int, int>> g[N];

void dfs(int v, int p) {
    vector<pair<int, int>> adj;
    for (auto [to, w]: g[v]) {
        if (to != p) {
            dfs(to, v);
            adj.emplace_back(to, w);
        }
    }
    for (int k = 0; k < n; ++k) {
        vector<ll> nw;
        ll ans = 0;
        for (auto [to, w]: adj) {
            ans += dp[to][k] + w;
            if (k) {
                nw.push_back(dp[to][k - 1] - dp[to][k] - w);
            }
        }
        sort(all(nw));
        for (int i = 0; i < min((int)size(nw), k); ++i) {
            if (nw[i] < 0)
                ans += nw[i];
        }
        dp[v][k] = ans;
        if (k) {
            dp[v][k] = min(dp[v][k], dp[v][k - 1]);
        }
    }
}

vector <ll> minimum_closure_costs(int nn, vector<int> uu, vector<int> vv, vector<int> ww) {
    n = nn;
    for (int i = 0; i < n - 1; ++i) {
        A[i] = uu[i], B[i] = vv[i], W[i] = ww[i];
        g[A[i]].emplace_back(B[i], W[i]);
        g[B[i]].emplace_back(A[i], W[i]);
    }
    vector <ll> ans;
    dfs(0, -1);
    for (int i = 0; i < n; ++i) {
        ans.push_back(dp[0][i]);
    }
    return ans;
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 7
• Subtask 3: 0 / 14
• Subtask 4: 0 / 10
• Subtask 5: 0 / 17
• Subtask 6: 0 / 25
• Subtask 7: 0 / 22