Submission #531071

#	Time	Username	Problem	Language	Result	Execution time	Memory
531071		Alex_tz307	Paprike (COI18_paprike)	C++17	100 / 100	93 ms	22208 KiB

paprike

#include <bits/stdc++.h>

using namespace std;

const int kN = 1e5;
int n, k, h[1 + kN];
vector<int> g[1 + kN];

struct state {
  int minCuts;
  int64_t minSum;
} dp[1 + kN];

void dfs(int u, int par) {
  dp[u].minCuts = 0;
  dp[u].minSum = h[u];
  priority_queue<int64_t> pq;
  for (int v : g[u]) {
    if (v != par) {
      dfs(v, u);
      dp[u].minCuts += dp[v].minCuts;
      dp[u].minSum += dp[v].minSum;
      pq.emplace(dp[v].minSum);
    }
  }
  while (dp[u].minSum > k) {
    dp[u].minCuts += 1;
    dp[u].minSum -= pq.top();
    pq.pop();
  }
}

void testCase() {
  cin >> n >> k;
  for (int i = 1; i <= n; ++i) {
    cin >> h[i];
  }
  for (int i = 1; i < n; ++i) {
    int u, v;
    cin >> u >> v;
    g[u].emplace_back(v);
    g[v].emplace_back(u);
  }
  dfs(1, 0);
  cout << dp[1].minCuts << '\n';
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  int tests = 1;
  for (int tc = 0; tc < tests; ++tc) {
    testCase();
  }
  return 0;
}

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