Submission #981711

#	Time	Username	Problem	Language	Result	Execution time	Memory
981711		duckindog	Magic Tree (CEOI19_magictree)	C++17	100 / 100	122 ms	40632 KiB

magictree

#include <bits/stdc++.h>

using namespace std;

const int N = 100'000 + 10;
int n, m, k;
vector<int> ad[N];
int d[N], w[N];

map<int, long long> f[N];
void merge(auto& x, auto& y) { 
  if (x.size() < y.size()) swap(x, y);
  for (const auto& it : y) x[it.first] += it.second;
}
void dfs(int u, int p = 0) { 
  for (const auto& v : ad[u]) { 
    if (v == p) continue;
    dfs(v, u);
    merge(f[u], f[v]);
  }

  long long sum = w[u];
  auto it = f[u].lower_bound(d[u] + 1);
  while (it != f[u].end()) { 
    if (sum > it->second) { 
      sum -= it->second;
      f[u].erase(it);
    } else { it->second -= sum; break; }
    it = f[u].lower_bound(d[u] + 1);
  }
  f[u][d[u]] += w[u];
}

int32_t main() { 
  cin.tie(0)->sync_with_stdio(0);

  cin >> n >> m >> k;
  for (int i = 2; i <= n; ++i) { 
    int v; cin >> v;
    ad[i].push_back(v);
    ad[v].push_back(i);
  }
  for (int i = 1; i <= m; ++i) { 
    int v; cin >> v >> d[v] >> w[v];
  }
  
  dfs(1);

  long long answer = 0;
  for (const auto& x : f[1]) answer += x.second;

  cout << answer << "\n";
}

Compilation message (stderr)

magictree.cpp:11:12: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
   11 | void merge(auto& x, auto& y) {
      |            ^~~~
magictree.cpp:11:21: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
   11 | void merge(auto& x, auto& y) {
      |                     ^~~~

• Subtask 1: 6 / 6
• Subtask 2: 3 / 3
• Subtask 3: 11 / 11
• Subtask 4: 12 / 12
• Subtask 5: 16 / 16
• Subtask 6: 13 / 13
• Subtask 7: 22 / 22
• Subtask 8: 17 / 17