Submission #898395

#	Time	Username	Problem	Language	Result	Execution time	Memory
898395		limbo16	Magic Tree (CEOI19_magictree)	C++14	100 / 100	125 ms	52356 KiB

magictree

#include <bits/stdc++.h>

#define all(a) a.begin(), a.end()
#define allr(a) a.rbegin(), a.rend()
#define len(a) (int)a.size()
#define endl '\n'
#define int long long

using namespace std;
const int INF = 1e18;

const int MAXN = 2e5 + 100;
vector<int> g[MAXN];
map<int, int> stored_map[MAXN];
map<int, int> global_map;
int subtree[MAXN], fruit_time[MAXN], fruit_weight[MAXN], has_fruit[MAXN];

void dfs1(int u) {
    subtree[u] = 1;
    for (int v : g[u]) {
        dfs1(v);
        subtree[u] += subtree[v];
    }
}

void dfs2(int u, bool store_info = true) {
    int max_subtree_v = -1;
    for (int v : g[u]) {
        if (max_subtree_v == -1 || subtree[v] > subtree[max_subtree_v])
            max_subtree_v = v;
    }
    for (int v : g[u]) {
        if (v != max_subtree_v)
            dfs2(v, true);
    }
    global_map.clear();
    if (max_subtree_v != -1)
        dfs2(max_subtree_v, false);
    for (int v : g[u]) {
        if (v != max_subtree_v) {
            for (auto [x, dif] : stored_map[v])
                global_map[x] += dif;
        }
    }
    if (has_fruit[u]) {
        global_map[fruit_time[u]] += fruit_weight[u];
        auto it = global_map.upper_bound(fruit_time[u]);
        int acc = 0;
        while (it != global_map.end()) {
            acc += it->second;
            if (acc <= fruit_weight[u]) {
                global_map.erase(it++);
            } else {
                it->second = acc - fruit_weight[u];
                break;
            }
        }
    }
    if (store_info)
        stored_map[u] = global_map;
}

int32_t main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
#ifdef MY_DEBUG
    freopen("../input.txt", "r", stdin);
    freopen("../output.txt", "w", stdout);
#endif
    int n, m, k;
    cin >> n >> m >> k;
    for (int i = 1; i < n; i++) {
        int p;
        cin >> p;
        g[p - 1].push_back(i);
    }
    for (int i = 0; i < m; i++) {
        int u;
        cin >> u;
        has_fruit[u - 1] = true;
        cin >> fruit_time[u - 1] >> fruit_weight[u - 1];
    }
    dfs1(0);
    dfs2(0);
    int ans = 0;
    for (auto [x, dif] : stored_map[0])
        ans += dif;
    cout << ans;
}

Compilation message (stderr)

magictree.cpp: In function 'void dfs2(long long int, bool)':
magictree.cpp:41:23: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   41 |             for (auto [x, dif] : stored_map[v])
      |                       ^
magictree.cpp: In function 'int32_t main()':
magictree.cpp:86:15: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   86 |     for (auto [x, dif] : stored_map[0])
      |               ^

• 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