Submission #1237680

#	Time	Username	Problem	Language	Result	Execution time	Memory
1237680		badge881	Magic Tree (CEOI19_magictree)	C++20	100 / 100	78 ms	28484 KiB

magictree

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

class Solver
{
public:
    Solver(int n, int m, int k)
        : n(n), m(m), k(k), listAdj(n + 1), fruitDays(n + 1, -1), fruitAmount(n + 1, 0) {}

    void addEdge(int parent, int child)
    {
        listAdj[parent].push_back(child);
    }

    void addFruit(int node, int day, int quantity)
    {
        fruitDays[node] = day;
        fruitAmount[node] = quantity;
    }

    int compute()
    {
        auto remainingJuice = dfs(1);
        int total = 0;
        for (auto &[day, amount] : remainingJuice)
            total += amount;
        return total;
    }

private:
    int n, m, k;
    vector<vector<int>> listAdj;
    vector<int> fruitDays;
    vector<int> fruitAmount;

    map<int, int> dfs(int node)
    {
        map<int, int> juiceMap;

        for (int child : listAdj[node])
        {
            auto childMap = dfs(child);

            if (childMap.size() > juiceMap.size())
                swap(childMap, juiceMap);

            for (auto &[d, a] : childMap)
            {
                juiceMap[d] += a;
            }
        }

        int day = fruitDays[node];
        int qty = fruitAmount[node];

        if (qty > 0)
        {
            juiceMap[day] += qty;

            int toRemove = qty;
            auto it = juiceMap.upper_bound(day);

            while (it != juiceMap.end() && toRemove > 0)
            {
                if (toRemove >= it->second)
                {
                    toRemove -= it->second;
                    it = juiceMap.erase(it);
                }
                else
                {
                    it->second -= toRemove;
                    break;
                }
            }
        }

        return juiceMap;
    }
};

signed main()
{
    int n, m, k;
    scanf("%lld%lld%lld", &n, &m, &k);

    Solver solver(n, m, k);

    for (int i = 2; i <= n; ++i)
    {
        int parent;
        scanf("%lld", &parent);
        solver.addEdge(parent, i);
    }

    for (int i = 0; i < m; ++i)
    {
        int node, day, qty;
        scanf("%lld%lld%lld", &node, &day, &qty);
        solver.addFruit(node, day, qty);
    }
    printf("%lld\n", solver.compute());
}

Compilation message (stderr)

magictree.cpp: In function 'int main()':
magictree.cpp:86:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   86 |     scanf("%lld%lld%lld", &n, &m, &k);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
magictree.cpp:93:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   93 |         scanf("%lld", &parent);
      |         ~~~~~^~~~~~~~~~~~~~~~~
magictree.cpp:100:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  100 |         scanf("%lld%lld%lld", &node, &day, &qty);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• 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