Submission #1029018

#	Time	Username	Problem	Language	Result	Execution time	Memory
1029018		GrindMachine	Jobs (BOI24_jobs)	C++17	100 / 100	205 ms	71700 KiB

Main

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) (int)a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x,y) ((x+y-1)/(y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a,b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a,b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#endif

/*

refs:
edi

*/

const int MOD = 1e9 + 7;
const int N = 3e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

struct S{
    ll m,s;
    S(ll m_, ll s_){
        m = m_, s = s_;
    }
    bool operator<(const S& f) const{
        bool g1 = s >= 0;
        bool g2 = f.s >= 0;
        if(g1 != g2) return g1 > g2;
        if(g1){
            return m > f.m;
        }
        else{
            return s-m > f.s-f.m;
        }
    }
    bool operator>(const S& f) const{
        bool g1 = s >= 0;
        bool g2 = f.s >= 0;
        if(g1 != g2) return g1 < g2;
        if(g1){
            return m < f.m;
        }
        else{
            return s-m < f.s-f.m;
        }
    }
};

S merge(S &x, S &y){
    auto [d1,s1] = x;
    auto [d2,s2] = y;
    ll d3 = min(d1,s1+d2);
    ll s3 = s1+s2;
    return S(d3,s3);
}

vector<ll> a(N);
vector<ll> adj[N];
priority_queue<S,vector<S>,greater<S>> pq[N];

void dfs1(ll u){
    trav(v,adj[u]){
        dfs1(v);
    }

    trav(v,adj[u]){
        if(sz(pq[u]) < sz(pq[v])){
            swap(pq[u],pq[v]);
        }

        while(!pq[v].empty()){
            pq[u].push(pq[v].top());
            pq[v].pop();
        }
    }

    S curr(min(a[u],0ll),a[u]);

    while(!pq[u].empty()){
        auto tp = pq[u].top();
        if(curr < tp) break;
        pq[u].pop();
        curr = merge(curr,tp);
    }

    pq[u].push(curr);
}

void solve(int test_case)
{
    ll n,m; cin >> n >> m;
    rep1(i,n){
        ll x,p; cin >> x >> p;
        a[i] = x;
        adj[p].pb(i);
    }

    dfs1(0);
    ll om = m;
    ll ans = 0;

    while(!pq[0].empty()){
        auto [mnp,sum] = pq[0].top();
        pq[0].pop();
        if(m+mnp >= 0){
            m += sum;
            amax(ans,m);
        }
        else{
            break;
        }
    }

    ans -= om;
    amax(ans,0ll);
    cout << ans << endl;
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;

    rep1(i, t) {
        solve(i);
    }

    return 0;
}

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