Submission #1155889

#	Time	Username	Problem	Language	Result	Execution time	Memory
1155889		VMaksimoski008	Museum (CEOI17_museum)	C++20	20 / 100	3098 ms	91876 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;

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

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];
    }

    int m = sub[u];
    dp[u].resize(m+1, vector<ll>(2, 1e15));
    ll tmp[m+1][2];

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

        for(int i=1; i<=sub[u]; i++) {
            for(int j=1; i+j<=sub[u]&&j<=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=0; i<=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 });
    }

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

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