Submission #1055821

#	Time	Username	Problem	Language	Result	Execution time	Memory
1055821		hotboy2703	Meetings (JOI19_meetings)	C++17	100 / 100	390 ms	1148 KiB

meetings

#include "meetings.h"

#include<bits/stdc++.h>
using ll = long long;
using namespace std;
#define pll pair <ll,ll>
#define fi first
#define se second
#define MP make_pair
#define sz(a) (ll((a).size()))
#define BIT(mask,i) (((mask) >> (i))&1)
#define MASK(i) (1LL << (i))
const ll MAXN = 2010;
mt19937_64 rng(69420);
ll random(ll l,ll r){
    return rng()%(r-l+1)+l;
}
vector <ll> sub[MAXN];
ll lose[MAXN];
void dfs(ll u){
    sort(sub[u].begin(),sub[u].end(),[](ll x,ll y){return lose[x]<lose[y];});
    for (auto v:sub[u]){
        if (lose[v] == lose[sub[u][0]]){
            // cout<<"BR "<<u<<' '<<v<<endl;
            Bridge(min(u,v),max(u,v));
            dfs(v);
        }
        else break;
    }
}
void solve(vector <ll> all){
    if (sz(all)<2)return;
    sort(all.begin(),all.end());
    ll x = all[random(0,sz(all)-1)];
    ll y = x;
    while (y==x)y=all[random(0,sz(all)-1)];
    map <ll,vector <ll> > mp;
    for (auto z:all){
        if (z!=x&&z!=y){
            ll tmp = Query(x,y,z);
            mp[tmp].push_back(z);
        }
    }
    vector <ll> path;
    path.push_back(x);
    path.push_back(y);
    for (auto z:mp)if (z.fi != x && z.fi != y){
        path.push_back(z.fi);
    }
    stable_sort(path.begin(),path.end(),[&](ll a1,ll a2)->bool{
        if (a1==x)return 1;
        if (a2==x)return 0;
        return Query(x,a1,a2)==a1;
    });
    for (ll j = 0;j + 1 < sz(path);j ++){
        // cout<<path[j]<<' '<<path[j+1]<<'\n';
        Bridge(min(path[j],path[j+1]),max(path[j],path[j+1]));
    }
    for (auto z:mp){
        vector <ll> tmp = z.se;
        tmp.push_back(z.fi);
        sort(tmp.begin(),tmp.end());
        tmp.resize(unique(tmp.begin(),tmp.end())-tmp.begin());
        solve(tmp);
    }
}
void Solve(int n) {
    vector <ll> all(n);
    iota(all.begin(),all.end(),0);
    solve(all);
}

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