제출 #815444

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
815444		stefanopulos	Paprike (COI18_paprike)	C++17	100 / 100	67 ms	23848 KiB

paprike

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <bits/stdc++.h>
 
using namespace std;
using namespace __gnu_pbds;
 
typedef long long ll;
typedef long double ldb;
 
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef pair<ldb,ldb> pdd;

#define ff(i,a,b) for(int i = a; i <= b; i++)
#define fb(i,b,a) for(int i = b; i >= a; i--)
#define trav(a,x) for(auto& a : x)
 
#define sz(a) (int)(a).size()
#define fi first
#define se second
#define pb push_back
#define lb lower_bound
#define ub upper_bound
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
 
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

template<typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

// os.order_of_key(k) the number of elements in the os less than k
// *os.find_by_order(k)  print the k-th smallest number in os(0-based)

const int mod = 1000000007;
const int inf = 1e9 + 5;
const int mxN = 200005; 

int n, k;
int niz[mxN];

vector<int> g[mxN];

int br = 0;
ll kol[mxN];
void dfs(int v, int p){

    kol[v] = niz[v]; vector<ll> vec; 
    for(auto u : g[v]){
        if(u != p){
            dfs(u, v);
            kol[v] += kol[u]; vec.pb(kol[u]);
        }
    }

    sort(rall(vec));
    for(auto c : vec){
        if(kol[v] > k){
            kol[v] -= c;
            br += 1;
        }
    }

}

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

    cin >> n >> k;
    ff(i,1,n)cin >> niz[i];
    ff(i,1,n - 1){
        int u, v;
        cin >> u >> v;
        g[u].pb(v);
        g[v].pb(u);
    }

    dfs(1, -1);

    cout << br << '\n';

    return 0;
}
/*



// probati bojenje sahovski
*/
 
 
 
 
 

• Subtask 1: 11 / 11
• Subtask 2: 13 / 13
• Subtask 3: 27 / 27
• Subtask 4: 49 / 49