Submission #154951

#	Time	Username	Problem	Language	Result	Execution time	Memory
154951		Mercenary	Meetings (JOI19_meetings)	C++14	100 / 100	1403 ms	16848 KiB

meetings

#include "meetings.h"
#include<bits/stdc++.h>
#define pb push_back
using namespace std;

const int maxn = 2e3 + 4;
int L[maxn][maxn];

int LCA(int u , int v){
    if(u == 0 || v == 0)return 0;
    if(u == v)return u;
    if(u > v)swap(u , v);
    if(L[u][v] != -1)return L[u][v];
    return L[u][v] = Query(0 , u , v);
}

void Solve(int root , vector<int> child){
//    for(int c : child)cout << c << " ";cout << endl;
    if((int)child.size() <= 1)return;
    map<int,vector<int>> mmap;
    int u = child[rand() % child.size()];
    while(u == root)u = child[rand() % child.size()];
    vector<int> can;
    for(int c : child){
        int a = LCA(c , u);
        if(a == c)
            can.pb(c);
        mmap[a].pb(c);
    }
    sort(can.begin(),can.end(),[&](const int & x , const int & y){
            return LCA(x , y) == x;
         });
    for(int i = 0 ; i < (int)can.size() - 1 ; ++i){
        Bridge(min(can[i] , can[i + 1]) , max(can[i] , can[i + 1]));
    }
    for(auto& c : mmap)Solve(c.first , c.second);
}

void Solve(int n) {
    srand(time(0));
    memset(L,-1,sizeof L);
    vector<int> v(n);
    for(int i = 0 ; i < n ; ++i)v[i] = i;
    Solve(0 , v);
}

• Subtask 1: 7 / 7
• Subtask 2: 10 / 10
• Subtask 3: 12 / 12
• Subtask 4: 71 / 71