Submission #1209303

#	Time	Username	Problem	Language	Result	Execution time	Memory
1209303		PagodePaiva	Closing Time (IOI23_closing)	C++20	35 / 100	75 ms	29252 KiB

closing

#include "closing.h"
#include<bits/stdc++.h>

using namespace std;
const long long N = 200010;

vector <pair <long long, long long>> g[N];
long long mark[N];
long long custox[N], custoy[N];

void dfs_x(int v, int p){
    for(auto [x, w] : g[v]){
        if(x == p)
            continue;
        custox[x] = custox[v] + w;
        dfs_x(x, v);
    }
    return;
}

void dfs_y(int v, int p){
    for(auto [x, w] : g[v]){
        if(x == p)
            continue;
        custoy[x] = custoy[v] + w;
        dfs_y(x, v);
    }
    return;
}

int l[N], r[N];

int max_score(int n, int X, int Y, long long k,
              std::vector<int> U, std::vector<int> V, std::vector<int> W){
    for(int i = 0;i < n;i++){
        g[i].clear();
        mark[i] = 0;
        custox[i] = custoy[i] = 0;
    }
    for(long long i = 0;i < n-1;i++){
        g[U[i]].push_back({V[i], W[i]});
        g[V[i]].push_back({U[i], W[i]});
    }
    priority_queue <pair <long long, long long>> pq;
    pq.push({0, X});
    pq.push({0, Y});
    long long ans = 0, sum = 0;;
    while(!pq.empty()){
        auto [w, v] = pq.top();
        pq.pop();
        if(mark[v])
            continue;
        w *= -1;
        if(sum+w > k){
            break;
        }
        sum += w;
        ans++;
        mark[v] = 1;
        for(auto [x, ww] : g[v]){
            if(mark[x])
                continue;
            pq.push({-(ww+w), x});
        }
    }
    dfs_x(X, X);
    dfs_y(Y, Y);
    for(int i = 0;i < n;i++){
        l[i] = min(custox[i], custoy[i]);
        r[i] = max(custox[i], custoy[i]) - l[i];
        //cout << l[i] << ' ' << r[i] << '\n';
        mark[i] = 0;
    }
    priority_queue <array <long long, 3>> pqq;
    long long res = 0;
    long long custo = 0;
    for(int i = X;i <= Y;i++){
        pqq.push({-r[i], i, 1ll});
        custo += l[i];
        mark[i] = 1;
        res++;
    }
    if(custo > k)
        return ans;
    if(X > 0){
        pqq.push({-l[X-1], X-1, 0});
    }
    if(Y < n-1){
        pqq.push({-l[Y+1], Y+1, 0});
    }
    while(!pqq.empty()){
        auto [val, v, tp] = pqq.top();
        pqq.pop();
        val *= -1;
        //cout << val << ' ' << v << ' ' << tp << '\n';   
        if(val+custo > k)
            break;
        custo += val;
        res++;
        if(tp == 0){
            mark[v] = 1;
            pqq.push({-r[v], v, 1ll});
            for(auto [x, w] : g[v]){
                if(mark[x])
                    continue;
                mark[x] = 1;
                pqq.push({-l[x], x, 0ll});
            }
        }
    }
    ans = max(res, ans);
    return ans;
}

• Subtask 0: 0 / 0
• Subtask 1: 0 / 8
• Subtask 2: 9 / 9
• Subtask 3: 12 / 12
• Subtask 4: 14 / 14
• Subtask 5: 0 / 9
• Subtask 6: 0 / 11
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 17