Submission #1155917

#	Time	Username	Problem	Language	Result	Execution time	Memory
1155917		VMaksimoski008	Museum (CEOI17_museum)	C++20	80 / 100	3097 ms	216120 KiB

museum

#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e4 + 5;

int dp[2][maxn][maxn], dep[maxn], tmp[2][maxn];
vector<pair<int, int> > G[maxn];
int n, k, r, sub[maxn];

void dfs(int u, int p) {
    sub[u] = 1;

    for(auto [v, w] : G[u]) {
        if(v == p) continue;
        dep[v] = dep[u] + w;
        dfs(v, u);
        sub[u] += sub[v];
    }

    for(int i=0; i<=sub[u]; i++)
        dp[0][u][i] = dp[1][u][i] = 1e9;
    dp[0][u][0] = 0;
    dp[0][u][1] = 0;
    dp[1][u][1] = -dep[u];

    sub[u] = 1;
    for(auto [v, w] : G[u]) {
        if(v == p) continue;
        for(int i=0; i<=min(k, sub[u]+sub[v]); i++) {
            tmp[0][i] = dp[0][u][i];
            tmp[1][i] = dp[1][u][i];
        }

        for(int i=1; i<=min(k, sub[u]+sub[v]); i++) {
            for(int j=1; i+j<=min(k, sub[u]+sub[v])&&j<=min(k, sub[v]); j++) {
                tmp[0][i+j] = min(tmp[0][i+j], dp[0][u][i] + dp[0][v][j] + 2 * w);
                tmp[1][i+j] = min(tmp[1][i+j], dp[1][u][i] + dp[0][v][j] + 2 * w);
                tmp[1][i+j] = min(tmp[1][i+j], dp[0][u][i] + dp[1][v][j] + 2 * w);
            }
        }

        for(int i=1; i<=min(k, sub[u]+sub[v]); i++) {
            dp[0][u][i] = tmp[0][i];
            dp[1][u][i] = tmp[1][i];
        }

        sub[u] += sub[v];
    }
}

signed main() {
    ios_base::sync_with_stdio(false);
    cout.tie(0); cin.tie(0);

    cin >> n >> k >> r;
    for(int i=1; i<n; i++) {
        int a, b, w; cin >> a >> b >> w;
        G[a].push_back({ b, w });
        G[b].push_back({ a, w });
    }

    dfs(r, r);
    cout << dp[1][r][k] << '\n';
}

• Subtask 1: 20 / 20
• Subtask 2: 25 / 25
• Subtask 3: 35 / 35
• Subtask 4: 0 / 20