제출 #738407

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
738407		GrindMachine	Museum (CEOI17_museum)	C++17	0 / 100	297 ms	82372 KiB

museum

// Om Namah Shivaya

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x, y) ((x + y - 1) / (y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i, n) for(int i = 0; i < n; ++i)
#define rep1(i, n) for(int i = 1; i <= n; ++i)
#define rev(i, s, e) for(int i = s; i >= e; --i)
#define trav(i, a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a, b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a, b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif

/*



*/

const int MOD = 1e9 + 7;
const int N = 20 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

vector<pii> adj[N];
int dis[N][N];

void dfs(int u, int p, int s) {
    for (auto [v, w] : adj[u]) {
        if (v == p) conts;
        dis[s][v] = dis[s][u] + w;
        dfs(v, u, s);
    }
}

void solve(int test_case)
{
    int n, k, r; cin >> n >> k >> r;
    r--;

    rep1(i, n - 1) {
        int u, v, w; cin >> u >> v >> w;
        u--, v--;
        adj[u].pb({v, w}), adj[v].pb({u, w});
    }

    rep(u, n) {
        dfs(u, -1, u);
    }

    int dp[1 << n][n];
    rep(mask, 1 << n) {
        rep(i, n) {
            dp[mask][i] = inf1;
        }
    }

    dp[1 << r][r] = 0;

    rep(mask, 1 << n) {
        rep(i, n) {
            if (dp[mask][i] >= inf1) conts;
            rep(j, n) {
                if (!(mask & (1 << j))) {
                    amin(dp[mask | (1 << j)][j], dp[mask][i] + dis[i][j]);
                }
            }
        }
    }

    int ans = inf1;
    rep(mask, 1 << n) {
        rep(i, k) {
            if (setbits(mask) == k) {
                amin(ans, dp[mask][i]);
            }
        }
    }

    cout << ans << endl;
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;

    rep1(i, t) {
        solve(i);
    }

    return 0;
}

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