Submission #1240442

#	Time	Username	Problem	Language	Result	Execution time	Memory
1240442		mychecksedad	Longest Trip (IOI23_longesttrip)	C++17	30 / 100	4 ms	420 KiB

longesttrip

#include "longesttrip.h"
#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define all(x) x.begin(),x.end()
#define vi vector<int>
#define pii pair<int,int>
#define ff first
#define ss second

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

int rn(int l, int r){
  return uniform_int_distribution<int>(l,r)(rng);
}

int ask(int u, int v){
  return are_connected(vi{u}, vi{v});
}

std::vector<int> longest_trip(int n, int D){
  vi p;
  for(int i = 1; i <= n; ++i){
    p.pb(i-1);
    swap(p[i-1], p[rn(0, i-1)]);
  }

  vi A, B;
  A.pb(p[0]);
  for(int i = 1; i < n; ++i){
    int v = p[i];
    int u = A.back();
    if(ask(u, v)){
      A.pb(v);
    }else if(B.size()){
      u = B.back();
      if(ask(u, v)){
        B.pb(v);
      }else{
        reverse(all(B));
        for(int x: B) A.pb(x);
        B.clear();
        B.pb(v);
      }
    }else B.pb(v);
  }
  if(B.size()>A.size()) A.swap(B);
  return A;
}

• Subtask 0: 0 / 0
• Subtask 1: 5 / 5
• Subtask 2: 0 / 10
• Subtask 3: 25 / 25
• Subtask 4: 0 / 60