Submission #1064852

#	Time	Username	Problem	Language	Result	Execution time	Memory
1064852		Boomyday	Jobs (BOI24_jobs)	C++17	43 / 100	2096 ms	956336 KiB

Main

//
// Created by adavy on 8/18/2024.
//
#include <bits/stdc++.h>


using namespace std;

using ll = long long;
const ll MOD = 1e9 + 7;

#define int ll

#define f first
#define s second

pair<ll,ll> merge(pair<ll,ll> a, pair<ll,ll> b){
    return {min(a.f,b.f),a.s-max(a.f,b.f)+b.s};
}


struct prs{
    set<pair<ll,ll>> ps;
    void insert(pair<ll,ll> p){
        /*
        cout << "ps: " << endl;
        for(auto& itm:ps){
            cout << itm.f << " " << itm.s << endl;
        }
        cout << "p: " << p.f << " " << p.s << endl;*/
        while(1){
            auto it = ps.lower_bound(p);
            if (it != ps.end()) {
                if (it-> f <= p.s){
                    p = merge(p,*it);
                    ps.erase(it);
                    continue;
                }
            }
            auto it2 = ps.upper_bound(p);
            if (it2 != ps.begin()){
                --it2;
                if (it2->s >= p.f){
                    p = merge(p,*it2);
                    ps.erase(it2);
                    continue;
                }
            }
            if (p.f > p.s){
                ps.clear();
                return;
            }
            ps.insert(p);

            break;
        }
    }
    void subtract(ll x){
        ll balance = -x;
        ll neg = balance;
        while (!ps.empty() && balance < 0){
            balance -= ps.begin()->f;
            neg = min(neg,balance);
            balance += ps.begin()->s;
            ps.erase(ps.begin());

        }
        if (balance >= 0){
            this->insert({-neg,balance-neg});
        }
    }
};

vector<vector<int>> adj;
vector<int> val;
vector<prs> sets;
vector<int> which;

void dfs(int v, int p){
    int maxsz = -1, maxch = -1;
    for(int u:adj[v]){
        if (u == p) continue;
        dfs(u,v);
        if (sets[u].ps.size() > maxsz){
            maxsz = sets[u].ps.size();
            maxch = u;
        }
    }
    if (maxsz == -1){
        which[v] = v;
    }
    else {
        which[v] = which[maxch];
    }
    for(int u:adj[v]){
        if (u==p || u == maxch) continue;
        for(auto& itm:sets[u].ps){
            sets[which[v]].insert(itm);
        }
    }
    if (val[v] > 0){
        sets[which[v]].insert({0LL,val[v]});
    }
    else {
        sets[which[v]].subtract(-val[v]);

    }
    // output v, sets[which[v]].ps

/*
    cout << "v: " << v << endl;
    for(auto& itm:sets[which[v]].ps){
      cout << itm.f << " " << itm.s << endl;
    }*/
}

signed main(){
    int N,s; cin >> N >> s;
    adj.resize(N+1);
    val.resize(N+1);
    sets.resize(N+1);
    which.resize(N+1,-1);
    val[0] = 0;
    for(int i=1;i<=N;++i){
        ll x,p; cin >> x >> p;
        val[i] = x;
        adj[p].push_back(i);
        adj[i].push_back(p);
    }
    dfs(0,-1);
    int t = s;
    for(auto& item:sets[which[0]].ps){
        if (t >= item.f){
            t -= item.f;
            t += item.s;
        }
    }
    cout << t-s << endl;





}

Compilation message (stderr)

Main.cpp: In function 'void dfs(ll, ll)':
Main.cpp:84:31: warning: comparison of integer expressions of different signedness: 'std::set<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} and 'll' {aka 'long long int'} [-Wsign-compare]
   84 |         if (sets[u].ps.size() > maxsz){
      |             ~~~~~~~~~~~~~~~~~~^~~~~~~

• Subtask 1: 0 / 11
• Subtask 2: 14 / 14
• Subtask 3: 0 / 15
• Subtask 4: 29 / 29
• Subtask 5: 0 / 31