Submission #578963

#	Time	Username	Problem	Language	Result	Execution time	Memory
578963		ddy888	Paprike (COI18_paprike)	C++17	100 / 100	85 ms	21868 KiB

paprike

#undef _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define pb push_back
#define fi first
#define si second
typedef pair<ll,ll> pi;
typedef tuple<int,int,int> ti;  
void debug_out() {cerr<<endl;}
template <typename Head, typename... Tail>
void debug_out(Head _H, Tail... _T) {cerr<<" "<<to_string(_H);debug_out(_T...);}
#define debug(...) cerr<<"["<<#__VA_ARGS__<<"]:",debug_out(__VA_ARGS__)
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int MAXN = 100010;

int n, k;
vector<int> g[MAXN];

int ans;
ll arr[MAXN];
ll sum[MAXN];

void dfs(int x, int p) {
    priority_queue<ll> hit;
    sum[x] = arr[x];
    for (auto i: g[x]) {
        if (i == p) continue;
        dfs(i, x);
        sum[x] += sum[i];
        hit.push(sum[i]);
    }
  
    while (hit.size() && sum[x] > k) {
        sum[x] -= hit.top();
        hit.pop();
        ++ans;
    }
}

int main() {
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0); 

    cin >> n >> k;
    for (int i = 1; i <= n; ++i) cin >> arr[i];
    for (int i = 1; i < n; ++i) {
        int u, v; cin >> u >> v;
        g[u].pb(v);
        g[v].pb(u);
    }
    dfs(1, 1);
    cout << ans;
    return 0;
}

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