Submission #541234

#	Time	Username	Problem	Language	Result	Execution time	Memory
541234		Victor	Parkovi (COCI22_parkovi)	C++17	0 / 110	192 ms	49216 KiB

Main

// #pragma GCC target ("avx,avx2,fma")
// #pragma GCC optimize ("Ofast,inline") // O1 - O2 - O3 - Os - Ofast
// #pragma GCC optimize ("unroll-loops")
#include <bits/stdc++.h>

using namespace std;

#define rep(i, a, b) for (int i = (a); i < (b); ++i)
#define per(i, a, b) for (int i = (b - 1); i >= (a); --i)
#define trav(a, x) for (auto &a : x)

#define all(x) x.begin(), x.end()
#define sz(x) x.size()
#define pb push_back
#define debug(x) cout << #x << " = " << x << endl

#define umap unordered_map
#define uset unordered_set

typedef pair<int, int> ii;
typedef pair<int, ii> iii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<vi> vvi;

typedef long long ll;
typedef pair<ll, ll> pll;
typedef vector<ll> vll;
typedef vector<pll> vpll;

const int INF = 1'000'000'007;

int k, n;
vpll graph[200005];
vll solution;
ll mid, max_dist[200005], to_park[200005], need[200005];

void dfs(ll u, ll p) {
    max_dist[u] = 0;
    to_park[u] = ll(1e16);
    need[u] = 0;

    trav(edge, graph[u]) {
        ll v, w;
        tie(v, w) = edge;
        if (v != p) {
            dfs(v,u);

            need[u] += need[v];

            max_dist[v] += w;
            to_park[v] += w;

            if (max_dist[v] > mid) {
                max_dist[v] = -1e16;
                to_park[v] = w;
                ++need[u];
                //cout<<"u = "<<u+1<<" v = "<<v+1<<endl;
                solution.pb(v);
            }

            //cout<<max_dist[u]<<" "<<to_park[u]<<" "<<max_dist[v]<<" "<<to_park[v]<<endl;
            if (max_dist[u] + to_park[v] <= mid) max_dist[u] = ll(-1e16); 
            if (max_dist[v] + to_park[u] > mid && max_dist[v] > max_dist[u]) max_dist[u] = max_dist[v];
            if (to_park[v] < to_park[u]) to_park[u] = to_park[v];
        }
    }

    //cout<<"u = "<<u+1<<" p = "<<p+1<<" max_dist = "<<max_dist[u]<<" to_park = "<<to_park[u]<<endl<<endl;
}

int main() {
    cin.tie(0)->sync_with_stdio(0);
    cin.exceptions(cin.failbit);

    cin >> n >> k;
    rep(i, 1, n) {
        int u, v, w;
        cin >> u >> v >> w;
        graph[--u].emplace_back(--v, w);
        graph[v].emplace_back(u, w);
    }

    ll lo = 0, hi = ll(16);
    while (lo != hi) {
        mid = (lo + hi) / 2;
        dfs(0, 0);

        if (sz(solution) <= k)
            hi = mid;
        else
            lo = mid + 1;
        //debug(sz(solution));
        //cout<<endl;
        solution.clear();
    }

    mid = lo;
    dfs(0, 0);
    set<ll> ans;
    trav(val,solution) ans.insert(val);

    rep(i,0,n) {
        if(sz(ans)==k) break;
        ans.insert(i);
    }

    cout<<mid<<endl;
    trav(val,ans)cout<<val+1<<' ';
    cout<<endl;
    return 0;
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:89:26: warning: comparison of integer expressions of different signedness: 'std::vector<long long int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   89 |         if (sz(solution) <= k)
      |                          ^
Main.cpp:104:19: warning: comparison of integer expressions of different signedness: 'std::set<long long int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  104 |         if(sz(ans)==k) break;
      |                   ^

• Subtask 1: 0 / 10
• Subtask 2: 0 / 10
• Subtask 3: 0 / 30
• Subtask 4: 0 / 60