Submission #869001

#	Time	Username	Problem	Language	Result	Execution time	Memory
869001		TB_	Museum (CEOI17_museum)	C++17	100 / 100	360 ms	3204 KiB

museum

#include <bits/stdc++.h>
using namespace std;

// #undef _GLIBCXX_DEBUG                // disable run-time bound checking, etc
// #pragma GCC optimize("Ofast,inline") // Ofast = O3,fast-math,allow-store-data-races,no-protect-parens
// #pragma GCC optimize ("unroll-loops")

// #pragma GCC target("bmi,bmi2,lzcnt,popcnt")                      // bit manipulation
// #pragma GCC target("movbe")                                      // byte swap
// #pragma GCC target("aes,pclmul,rdrnd")                           // encryption
// #pragma GCC target("avx,avx2,f16c,fma,sse3,ssse3,sse4.1,sse4.2") // SIMD

// #include <bits/extc++.h>
// using namespace __gnu_pbds;
// template<class T>using ordered_set = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;
// template<class T>using ordered_multiset = tree<T, null_type, less_equal<T>, rb_tree_tag,tree_order_statistics_node_update>;

#define ll long long
#define INF (ll)1e9+7
#define fo(i, n) for(ll i=0;i<((ll)n);i++)
#define deb(x) cout << #x << " = " << (x) << endl;
#define deb2(x, y) cout << #x << " = " << (x) << ", " << #y << " = " << (y) << endl
#define pb push_back
#define mp make_pair
#define F first
#define S second
#define LSOne(S) ((S) & (-S))
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
inline int readint(){ int v = 0; char c; while((c = getchar()) != EOF && c != ' ' && c != '\n'){ v *= 10; v += c - '0'; } return v; }
inline int readintsigned() { int v = 0; int sign = 1; char c = getchar(); if (c == '-') { sign = -1; } else { v += c - '0'; } while ((c = getchar()) != EOF && c != ' ' && c != '\n') { v *= 10; v += c - '0'; } return v * sign; }
inline string readstring() { string s; char c; while ((c = getchar()) != EOF && c != '\n' && c != ' ') { s.push_back(c); } return s; }
template <class result_t=std::chrono::milliseconds,class clock_t=std::chrono::steady_clock,class duration_t = std::chrono::milliseconds>
auto since(std::chrono::time_point<clock_t, duration_t> const& start){return std::chrono::duration_cast<result_t>(clock_t::now() - start);}
typedef pair<int, int> pii;
typedef pair<ll, ll> pl;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<pii> vpii;
typedef vector<pl> vpl;
typedef vector<vi> vvi;
typedef vector<vl> vvl;
typedef vector<vpii> vvpii;
typedef vector<vpl> vvpl;

vvpl adj(10001);


vvl dp(int u, int last = -1){
    vvl ans = {{0, 0}, {0, 0}};
    for(auto &[v, w] : adj[u]){
        if(v == last) continue;
        vvl res = dp(v, u);
        vl next(ans[0].size()+res[0].size(), INF);
        vl next2(max(ans[0].size()+res[1].size(), ans[1].size()+res[0].size()), INF);
        fo(i, ans[0].size()){
            fo(j, res[0].size()){
                next[i+j] = min(next[i+j], ans[0][i]+res[0][j]+(j?w*2:0));
            }
            fo(j, res[1].size()){
                next2[i+j] = min(next2[i+j], ans[0][i]+res[1][j]+(j?w:0));
            }
        }
        fo(i, ans[1].size()){
            fo(j, res[0].size()){
                next2[i+j] = min(next2[i+j], ans[1][i]+res[0][j]+(j?w*2:0));
            }
        }
        while(next[next.size()-1] == INF) next.pop_back(); 
        while(next2[next2.size()-1] == INF) next2.pop_back(); 
        swap(next, ans[0]);
        swap(next2, ans[1]);
    }
    return ans;
}

int main() {
    // cout << fixed << setprecision(20);
    // auto start = std::chrono::steady_clock::now(); // since(start).count()
    cin.tie(0)->sync_with_stdio(0);

    int n, k, x, a, b, c;
    cin >> n >> k >> x;
    fo(i, n-1){
        cin >> a >> b >> c;
        adj[--a].pb({--b, c});
        adj[b].pb({a, c});
    }
    cout << dp(x-1)[1][k];

    return 0;
}

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