Submission #535645

#	Time	Username	Problem	Language	Result	Execution time	Memory
535645		RaresFelix	Meetings (JOI19_meetings)	C++17	100 / 100	887 ms	3192 KiB

meetings

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

using namespace std;

using vi = vector<int>;

map<tuple<int, int, int>, int> Bfq;

int query(int a, int b, int c) {
    if(a > b) return query(b, a, c);
    if(a > c) return query(c, b, a);
    if(b > c) return query(a, c, b);
    if(Bfq.count({a, b, c})) return Bfq[{a, b, c}];
    int v = Query(a, b, c);
    Bfq[{a, b, c}] = v;
    return v;
}
#define pb push_back
void bridge(int a, int b) {
    Bridge(min(a, b), max(a, b));
}
void solve(int root, const vi& U, mt19937 rng) {
    if(U.empty()) return;
    map<int, vi> Altii;
    vi lant;
    int pivot = U[uniform_int_distribution<int>(0, U.size() - 1)(rng)];
    lant.pb(pivot);
    for(auto it : U) {
        if(it == pivot) continue;
        int v = query(root, it, pivot);
        if(v == it) lant.pb(v);
        else Altii[v].pb(it);
    }
    sort(lant.begin(), lant.end(), [&](auto a, auto b) {
       return query(root, a, b) == a;
    });
    bridge(root, lant[0]);
    for(int i = 0; i < lant.size() - 1; ++i)
        bridge(lant[i], lant[i+1]);
    for(auto &[rn, Un] : Altii)
        solve(rn, Un, rng);
}

void Solve(int N) {
    Bfq.clear();
    mt19937 rng(2);
    vi E;
    for(int i = 1; i < N; ++i) E.pb(i);
    solve(0, E, rng);
}

Compilation message (stderr)

meetings.cpp: In function 'void solve(int, const vi&, std::mt19937)':
meetings.cpp:39:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   39 |     for(int i = 0; i < lant.size() - 1; ++i)
      |                    ~~^~~~~~~~~~~~~~~~~

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