Submission #1155894

#	Time	Username	Problem	Language	Result	Execution time	Memory
1155894		VMaksimoski008	Museum (CEOI17_museum)	C++20	80 / 100	3072 ms	745960 KiB

museum

#include <bits/stdc++.h>
#define ar array
//#define int long long

using namespace std;

using ll = long long;
using pii = pair<int, int>;
using pll = pair<ll, ll>;

const int mod = 1e9 + 7;
const ll inf = 1e18;
const int maxn = 1e4 + 5;

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

void dfs(int u, int p) {
    sub[u] = 1;
    dp[u][0][0] = 0;
    dp[u][1][0] = 0;
    dp[u][1][1] = -dep[u];

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

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

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

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

signed main() {
    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 });
    }

    for(int i=1; i<=n; i++)
        for(int j=0; j<=k; j++)
            for(int k=0; k<2; k++) dp[i][j][k] = 1e9;
    dfs(r, r);
    cout << dp[r][k][1] << '\n';
}

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