Submission #509820

#	Time	Username	Problem	Language	Result	Execution time	Memory
509820		Rainbowbunny	Paths (RMI21_paths)	C++17	20 / 100	310 ms	26428 KiB

Main

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

using ll = long long;

#define int long long

const int MAXN = 3e5 + 5;

int n, k;
ll mx[MAXN], res[MAXN], cur[MAXN];
pair <ll, int> dp[MAXN];
vector <pair <int, ll> > Adj[MAXN];

void DFS(int node, int p = -1)
{
    for(auto x : Adj[node])
    {
        if(x.first == p)
        {
            continue;
        }
        DFS(x.first, node);
        dp[x.first].first += x.second;
        dp[node] = max(dp[node], dp[x.first]);
    }
    if(dp[node].second == 0)
    {
        dp[node] = make_pair(0, node);
    }
}

ll ans;
set <pair <ll, int> > First, Last;

void Add(pair <ll, int> P)
{
    cur[P.second] = P.first; 
    if((int)First.size() < k)
    {
        ans += P.first;
        First.insert(P);
    }
    else
    {
        pair <ll, int> tmp = *First.begin();
        if(tmp.first > P.first)
        {
            Last.insert(P);
        }
        else
        {
            First.erase(First.begin());
            ans -= tmp.first;
            First.insert(P);
            ans += P.first;
            Last.insert(tmp);
        }
    }
}

void Sub(pair <ll, int> P)
{
    if(Last.count(P))
    {
        Last.erase(P);
    }
    else
    {
        ans -= P.first;
        // assert(First.count(P));
        First.erase(P);
        if(!Last.empty())
        {
            ans += (*Last.rbegin()).first;
            First.insert(*Last.rbegin());
            Last.erase(*Last.rbegin());
        }
    }
}

void Print()
{
    for(auto x : First)
    {
        cout << x.first << ' ' << x.second << endl;
    }
    cout << "owo" << endl;
    for(auto x : Last)
    {
        cout << x.first << ' ' << x.second << endl;
    }        
    cout << endl;
}

void Reroot(int node, int p = -1, pair <ll, int> Good = make_pair(0ll, n))
{   
    // Print();
    res[node] = ans;
    vector <pair <ll, int> > tmp;
    vector <pair <ll, int> > Pref;
    vector <pair <ll, int> > Suff;
    for(int i = 0; i < (int)Adj[node].size(); i++)
    {
        int x = Adj[node][i].first;
        if(x == p)
        {
            tmp.push_back(Good);
        }
        else
        {
            tmp.push_back(dp[x]);
        }
        Pref.emplace_back(max(i == 0 ? make_pair(0ll, -1ll) : Pref[i - 1], tmp[i]));
    }
    Suff.resize((int)Pref.size());
    for(int i = (int)Adj[node].size() - 1; i >= 0; i--)
    {
        Suff[i] = max((i + 1 == (int)Adj[node].size()) ? make_pair(0ll, -1ll) : Suff[i + 1], tmp[i]);
    }
    for(int i = 0; i < (int)Adj[node].size(); i++)
    {
        int x = Adj[node][i].first;
        if(x == p)
        {
            continue;
        }
        pair <ll, int> tmp = make_pair(0, node);
        if(i)
        {
            tmp = max(tmp, Pref[i - 1]);
        }
        if(i + 1 != (int)Adj[node].size())
        {
            tmp = max(tmp, Suff[i + 1]);
        }
        Sub(tmp);
        Add(make_pair(tmp.first + Adj[node][i].second, tmp.second));

        Sub(dp[x]);
        Add(make_pair(dp[x].first - Adj[node][i].second, dp[x].second));

        Reroot(x, node, make_pair(tmp.first + Adj[node][i].second, tmp.second));

        Add(tmp);
        Sub(make_pair(tmp.first + Adj[node][i].second, tmp.second));

        Sub(make_pair(dp[x].first - Adj[node][i].second, dp[x].second));
        Add(dp[x]);
    }
}

signed main()
{
    // freopen("Input.txt", "r", stdin);
    // freopen("Output2.txt", "w", stdout);
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    cin >> n >> k;
    for(int i = 1; i < n; i++)
    {
        int u, v, c;
        cin >> u >> v >> c;
        Adj[u].emplace_back(v, c);
        Adj[v].emplace_back(u, c);
    }
    DFS(n);
    for(int i = 1; i <= n; i++)
    {
        mx[dp[i].second] = max(mx[dp[i].second], dp[i].first);
    }
    for(int i = 1; i <= n; i++)
    {
        if((int)Adj[i].size() == 1)
        {
            Add(make_pair(mx[i], i));
        }
    }
    Reroot(n);
    for(int i = 1; i <= n; i++)
    {
        cout << res[i] << '\n';
    }
}

• Subtask 1: 8 / 8
• Subtask 2: 0 / 11
• Subtask 3: 0 / 17
• Subtask 4: 0 / 20
• Subtask 5: 12 / 12
• Subtask 6: 0 / 32