Submission #1085816

#	Time	Username	Problem	Language	Result	Execution time	Memory
1085816		hqminhuwu	Parkovi (COCI22_parkovi)	C++14	30 / 110	554 ms	44228 KiB

Main

#include "bits/stdc++.h"
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair <ll,ll> pll;
typedef pair <int,int> pii;
typedef pair <int,pii> piii;

#define forr(_a,_b,_c) for(int _a = (_b); _a <= int (_c); ++_a)
#define ford(_a,_b,_c) for(int _a = (_b) + 1; _a --> int (_c);)
#define forf(_a,_b,_c) for(int _a = (_b); _a < int (_c); ++_a)
#define st first
#define nd second
#define pb push_back
#define mp make_pair
#define all(x) begin(x),end(x)
#define mask(i) (1LL << (i))
#define bit(x, i) (((x) >> (i)) & 1)
#define bp __builtin_popcountll
#define file "test"

template<class X, class Y>
    bool minz(X &x, const Y &y) {
        if (x > y) {
            x = y;
            return true;
        } return false;
    }
template<class X, class Y>
    bool maxz(X &x, const Y &y) {
        if (x < y) {
            x = y;
            return true;
        } return false;
    }

const int N = 5e5 + 5;
const ll oo = (ll) 2e16;
const ll mod = 1e9 + 7; // 998244353;

int deg[N], n, u, v, w, k;
ll dist[N], park[N];
stack <int> leaf;
int rem[N];
vector <pll> a[N];
vector <int> trace;

void dfs (int u, ll d, ll x){
    rem[u] = 1;
    dist[u] = -oo;
   // cout << u << " " << d << " ff" << endl;

    for (pll v : a[u]){
        if (rem[v.st]) continue;
        if (d + v.nd <= x){
            dfs(v.st, d + v.nd, x);
        } else {
            deg[v.st]--;
          //   cout << v.st << " " << deg[v.st] << endl;
            if (deg[v.st] == 1){
                leaf.push(v.st);
            }
        }
    }
}

ll solve(ll x){
    while (leaf.size()) leaf.pop();
    trace.clear();

    forr (i, 1, n){
        rem[i] = 0;
        dist[i] = 0;
        deg[i] = a[i].size();
        if (a[i].size() == 1){
            leaf.push(i);
        }
    }

    while (leaf.size()){
        int u = leaf.top();
        leaf.pop();
        if (rem[u]) continue;

        rem[u] = 1;
        ll tmp = oo;

        for (pll v : a[u]){
            if (rem[v.st]){
                dist[u] = max (dist[u], dist[v.st] + v.nd);
            }
        }

        for (pll v : a[u]){
            if (rem[v.st]) continue;
            tmp = min (tmp, dist[u] + v.nd);
        }

      //  cout << u << " " << tmp << endl;

        for (pll v : a[u]){
            if (rem[v.st]) continue;
            deg[v.st]--;
            if (deg[v.st] == 1)
                leaf.push(v.st);
        }

        if (tmp > x){
            trace.pb(u);
            dist[u] = -oo;
            for (pll v : a[u]){
                if (rem[v.st]) continue;
                if (v.nd <= x)
                    dfs(v.st, v.nd, x);
            }
        }
    }   

    return trace.size();
}

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0);
    #ifdef hqm
        freopen(file".inp", "r", stdin); freopen(file".out", "w", stdout);
    #endif

    cin >> n >> k;

    forf (i, 1, n){
        cin >> u >> v >> w;
        a[u].pb({v, w});
        a[v].pb({u, w});
    }

    ll l = 0, r = oo;
    //l = 60, r = 60;

    while (l < r){
        ll mid = (l + r) >> 1;
        if (solve(mid) > k)
            l = mid + 1;
        else r = mid;
    }        

    
    solve(l);

    cout << l << "\n";


    for (int u : trace){
        park[u] = 1;
    }

    k -= trace.size();

    forr (i, 1, n)
    if (!park[i] && k){
        k--;
        trace.pb(i);
    }

    sort(all(trace));

    for (int u : trace)
        cout << u << " ";
    
 
    return 0;
}
/*



*/

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