Submission #839887

#	Time	Username	Problem	Language	Result	Execution time	Memory
839887		AdamGS	Longest Trip (IOI23_longesttrip)	C++17	5 / 100	15 ms	348 KiB

longesttrip

#include "longesttrip.h"
#include<bits/stdc++.h>
using namespace std;
#define rep(a, b) for(int a = 0; a < (b); ++a)
#define st first
#define nd second
#define pb push_back
#define all(a) a.begin(), a.end()
vector<int>longest_trip(int n, int d) {
  mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
  vector<int>V, A, B;
  rep(i, n) {
    V.pb(i);
    swap(V[i], V[rng()%(i+1)]);
  }
  A.pb(V[0]);
  for(int i=1; i<n; ++i) {
    if(A.size()<B.size()) swap(A, B);
    if(B.size()==0) {
      B.pb(V[i]);
      continue;
    }
    vector<int>X, Y;
    X.pb(V[i]);
    if(rng()%2) {
      Y.pb(A.back());
      if(are_connected(X, Y)) A.pb(V[i]);
      else {
        Y[0]=B.back();
        if(are_connected(X, Y)) B.pb(V[i]);
        else {
          while(B.size()>0) {
            A.pb(B.back());
            B.pop_back();
          }
          B.pb(V[i]);
        }
      }
    } else {
      Y.pb(B.back());
      if(are_connected(X, Y)) B.pb(V[i]);
      else {
        Y[0]=A.back();
        if(are_connected(X, Y)) A.pb(V[i]);
        else {
          while(B.size()>0) {
            A.pb(B.back());
            B.pop_back();
          }
          B.pb(V[i]);
        }
      }
    }
    if(rng()%2) reverse(all(A));
    if(rng()%2) reverse(all(B));
  }
  if(A.size()>B.size()) swap(A, B);
  if(A.size()==0) return B;
  int po=0, ko=A.size();
  while(po<ko) {
    int sr=(po+ko)/2;
    vector<int>tmp;
    rep(i, sr+1) tmp.pb(A[i]);
    if(are_connected(tmp, B)) ko=sr; else po=sr+1;
  }
  if(ko==A.size()) return B;
  vector<int>X={A[po]};
  int po2=0, ko2=B.size()-1;
  while(po2<ko2) {
    int sr=(po2+ko2)/2;
    vector<int>tmp;
    rep(i, sr+1) tmp.pb(B[i]);
    if(are_connected(X, tmp)) ko2=sr; else po2=sr+1;
  }
  vector<int>ans;
  rep(i, A.size()) ans.pb(A[(i+po+1)%A.size()]);
  rep(i, B.size()) ans.pb(B[(i+po2)%B.size()]);
  return ans;
}

Compilation message (stderr)

longesttrip.cpp: In function 'std::vector<int> longest_trip(int, int)':
longesttrip.cpp:66:8: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   66 |   if(ko==A.size()) return B;
      |      ~~^~~~~~~~~~
longesttrip.cpp:4:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    4 | #define rep(a, b) for(int a = 0; a < (b); ++a)
      |                                    ^
longesttrip.cpp:76:3: note: in expansion of macro 'rep'
   76 |   rep(i, A.size()) ans.pb(A[(i+po+1)%A.size()]);
      |   ^~~
longesttrip.cpp:4:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    4 | #define rep(a, b) for(int a = 0; a < (b); ++a)
      |                                    ^
longesttrip.cpp:77:3: note: in expansion of macro 'rep'
   77 |   rep(i, B.size()) ans.pb(B[(i+po2)%B.size()]);
      |   ^~~

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