Submission #519763

#	Time	Username	Problem	Language	Result	Execution time	Memory
519763		Monarchuwu	Magic Tree (CEOI19_magictree)	C++17	100 / 100	158 ms	37712 KiB

magictree

#include<iostream>
#include<algorithm>
#include<vector>
#include<map>
using namespace std;
typedef long long ll;

typedef pair<int, int> pii;
#define ff first
#define ss second

const int N = 1e5 + 9;
int n, m, k;
int p[N];
pii fruit[N];
vector<int> g[N];

map<int, ll> dp[N];
namespace sub8 {
    int cnt(0), b[N];
    void dfs(int u) {
        for (int v : g[u]) {
            dfs(v);
            if (dp[u].size() < dp[v].size()) dp[u].swap(dp[v]);
            for (auto it : dp[v])
                dp[u][it.ff] += it.ss;
        }
        if (fruit[u].ff) {
            dp[u][fruit[u].ff] += fruit[u].ss;
            map<int, ll>::iterator it = dp[u].upper_bound(fruit[u].ff), tmp;

            for (ll diff = 0; it != dp[u].end(); it = tmp) {
                diff += it->ss;
                if (diff <= fruit[u].ss) {
                    // set dp[u][it->ff] = dp[u][fruit[u].ff], reset diff = 0
                    tmp = next(it);
                    dp[u].erase(it);
                }
                else {
                    // nothing change, recalc diff
                    it->ss = diff - fruit[u].ss;
                    break;
                }
            }
        }
    }
    void solve() {
        for (int i = 1; i <= n; ++i) if (fruit[i].ff) b[++cnt] = fruit[i].ff;
        sort(b + 1, b + cnt + 1);
        cnt = unique(b + 1, b + cnt + 1) - b;
        for (int i = 1; i <= n; ++i)
            if (fruit[i].ff) fruit[i].ff = lower_bound(b + 1, b + cnt, fruit[i].ff) - b;

        dfs(1);
        ll ans(0);
        for (auto it : dp[1]) ans += it.ss;
        cout << ans << '\n';
    }
}

int main() {
    cin.tie(NULL)->sync_with_stdio(false);
    cin >> n >> m >> k;
    for (int i = 2; i <= n; ++i) {
        cin >> p[i];
        g[p[i]].push_back(i);
    }
    for (int i = 0, v; i < m; ++i) {
        cin >> v;
        cin >> fruit[v].ff >> fruit[v].ss;
    }

    sub8::solve();
}
/**  /\_/\
 *  (= ._.)
 *  / >0  \>1
**/

• 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