Submission #867442

#	Time	Username	Problem	Language	Result	Execution time	Memory
867442		sleepntsheep	Biochips (IZhO12_biochips)	C++17	80 / 100	2044 ms	13004 KiB

biochips

#include <iostream>
#include <vector>
#include <algorithm>
#include <deque>
#include <set>
#include <utility>
#include <array>

using namespace std;
#define ALL(x) x.begin(), x.end()
#define ShinLena cin.tie(nullptr)->sync_with_stdio(false);
#define N 200050
using ll = long long;

int n, m, a[N], timer, dp[2][N];
vector<int> g[N];
vector<tuple<int, int, int>> v;

void dfs(int u)
{
    int in = timer++;
    for (auto v : g[u]) dfs(v);
    int out = timer++;
    v.emplace_back(out, in, a[u]);
}

void schedule()
{
    for (int j = 1; j <= m; ++j)
    {
        for (auto i = 1; i <= n; ++i)
        {
            auto [e, s, w] = v[i];
            int l = 0, r = i-1;
            dp[j&1][i] = dp[j&1][i-1];
            while (l <= r)
            {
                int y = (l+r)/2;
                if (get<0>(v[y]) < s)
                    dp[j&1][i] = max(dp[j&1][i], dp[!(j&1)][y] + w), l = y + 1;
                else r = y - 1;
            }
        }
    }
}

int main()
{
    ShinLena;
    cin >> n >> m;
    for (int p, i = 1; i <= n; ++i) cin >> p >> a[i], g[p].push_back(i);
    v={{-1e9,0,0}};dfs(0);
    sort(ALL(v));
    schedule();
    cout << dp[m&1][n];
    return 0;
}

• Subtask 1: 80 / 100