Submission #640588

#	Time	Username	Problem	Language	Result	Execution time	Memory
640588		baokhue232005	Paprike (COI18_paprike)	C++14	100 / 100	57 ms	22224 KiB

paprike

/*
#pragma GCC optimize("Ofast")
#pragma GCC target("avx,avx2,fma")
#pragma GCC optimize("unroll-loops")
*/
// lethal option

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

#define all(flg) flg.begin(), flg.end()
#define int long long
#define pb push_back
#define fi first
#define se second
#define endl "\n"
#define eb emplace_back
#define ii pair<int, int>
#define vi vector<int>
#define PI 3.141592653589793238462643383279502884
#define ll long long
#define ld long double
#define for1(i, ff, gg) for(int i = ff; i <= gg; ++i)
#define for2(i, ff, gg) for(int i = ff; i >= gg; --i)
const ll mod = 1e9 + 7;
const int maxN = 300005;
const ll oo = 1e18 + 7;
int n, a[maxN];
int x, y, z, k;

int ans = 0;
vector<int> vc[maxN];

int dfs(int node, int par){
    vector<int> eli;
    int sum = a[node];
    for(int cc : vc[node]) if(cc != par){
        eli.pb(dfs(cc, node));
    }
    sort(all(eli));
    for(int cc : eli) sum += cc;
    while(sum > k){
        sum -= eli.back(); eli.pop_back();
        ++ans;
    }
    return sum;
}

signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);
    cin >> n >> k;
    for1(i, 1, n) cin >> a[i];
    for1(i, 2, n){
        cin >> x >> y;
        vc[x].pb(y);
        vc[y].pb(x);
    }
    dfs(1, 0);
    cout << ans << endl;
}

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