Submission #696934

#	Time	Username	Problem	Language	Result	Execution time	Memory
696934		Do_you_copy	Parkovi (COCI22_parkovi)	C++17	0 / 110	666 ms	45372 KiB

Main

//Then
#include <bits/stdc++.h>
#define pb push_back
#define fi first
#define se second
#define faster ios_base::sync_with_stdio(0); cin.tie(0);
#define int long long
using namespace std;
using ll = long long;
using ld = long double;
using pii = pair <int, int>;
mt19937_64 Rand(chrono::steady_clock::now().time_since_epoch().count());
const int maxN = 3e5 + 1;
//const int Mod = 1e9 + 7;
//const int inf =
int n, k;
vector <pii> adj[maxN];
ll mid, cnt;
ll dp[maxN];
set <int> S;
bool visited[maxN];

void dfs(int u, int p){
    dp[u] = 0;
    int maxx = 0;
    visited[u] = 1;
    for (auto i: adj[u]){
        if (i.fi == p || i.se > mid) continue;
        dfs(i.fi, u);
        if (dp[i.fi] + i.se > mid){
            ++cnt;
            S.insert(i.fi);
            if (dp[u] < i.se){
                maxx = dp[u];
                dp[u] = i.se;
            }
            else maxx = max(maxx, i.se);
        }
        else{
            if (dp[u] < dp[i.fi] + i.se){
                maxx = dp[u];
                dp[u] = dp[i.fi] + i.se;
            }
            else maxx = max(maxx, dp[i.fi] + i.se);
        }
    }
    if (u == p && maxx + dp[u] > mid){
        S.insert(u); ++cnt;
    }
}

bool check(){
    S.clear();
    fill(visited + 1, visited + n + 1, 0);
    int res = 0;
    for (int i = 1; i <= n; ++i){
        cnt = 0;
        if (!visited[i]){
            dfs(i, i);
            if (!cnt){
                S.insert(i);
                ++res;
            }
            else res += cnt;
        }
    }
    return res <= k;
}

void Init(){
    cin >> n >> k;
    for (int i = 1; i < n; ++i){
        int u, v, w;
        cin >> u >> v >> w;
        adj[u].pb({v, w});
        adj[v].pb({u, w});
    }
    ll l = 1, r = 1e4;
    while (l < r){
        mid = (l + r) >> 1;
        if (check()) r = mid;
        else l = mid + 1;
    }
    mid = l;
    check();
    cout << l << "\n";
    for (int i = 1; i <= n; ++i){
        if (S.size() == k) break;
        S.insert(i);
    }
    for (auto i: S) cout << i << " ";
}

#define debug
#define taskname "test"
signed main(){
    faster
    if (fopen(taskname".inp", "r")){
        freopen(taskname".inp", "r", stdin);
        freopen(taskname".out", "w", stdout);
    }
    int tt = 1;
    //cin >> tt;
    while (tt--){
        Init();
    }
    if (fopen("timeout.txt", "r")){
        ofstream timeout("timeout.txt");
        timeout << signed(double(clock()) / CLOCKS_PER_SEC * 1000);
        timeout.close();
        #ifndef debug
        cerr << "Time elapsed: " << signed(double(clock()) / CLOCKS_PER_SEC * 1000) << "ms\n";
        #endif // debug
    }
}

Compilation message (stderr)

Main.cpp: In function 'void Init()':
Main.cpp:88:22: warning: comparison of integer expressions of different signedness: 'std::set<long long int>::size_type' {aka 'long unsigned int'} and 'long long int' [-Wsign-compare]
   88 |         if (S.size() == k) break;
      |             ~~~~~~~~~^~~~
Main.cpp: In function 'int main()':
Main.cpp:99:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   99 |         freopen(taskname".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:100:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  100 |         freopen(taskname".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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