Submission #958786

# Submission time Handle Problem Language Result Execution time Memory
958786 2024-04-06T16:11:07 Z nguyentunglam Longest Trip (IOI23_longesttrip) C++17
Compilation error
0 ms 0 KB
#include "longesttrip.h"
#include "grader.cpp"
#include<bits/stdc++.h>
using namespace std;

pair<int, int> Find (vector<int> a, vector<int> b) {
  if (!are_connected(a, b)) return make_pair(-1, -1);
  int l = 0, r = a.size() - 1, lastx = -1, lasty = -1;
  while (l <= r) {
    int mid = l + r >> 1;
    vector<int> ask;
    for(int i = 0; i <= mid; i++) ask.push_back(a[i]);
    if (are_connected(ask, b)) {
      lastx = mid;
      r = mid - 1;
    } else l = mid + 1;
  }
  l = 0, r = b.size() - 1;

  while (l <= r) {
    int mid = l + r >> 1;
    vector<int> ask;
    for(int i = 0; i <= mid; i++) ask.push_back(b[i]);
    if (are_connected(ask, a)) {
      lasty = mid;
      r = mid - 1;
    } else l = mid + 1;
  }
  assert(are_connected({a[lastx]}, {b[lasty]}));
  return make_pair(lastx, lasty);
}

vector<int> rev (vector<int> a) {
  reverse(a.begin(), a.end());
  return a;
}

vector<int> sum (vector<int> a, vector<int> b) {
  for(int &j : b) a.push_back(j);
  return a;
}

std::vector<int> longest_trip(int n, int d)
{
    if (d == 1) {
      vector<int> a, b;
      a.push_back(0);
      b.push_back(1);
      for(int i = 2; i < n; i++) {
        if (are_connected({a.back()}, {i})) a.push_back(i);
        else if (are_connected({b.back()}, {i})) b.push_back(i);
        else {
          reverse(b.begin(), b.end());
          for(int &j : b) a.push_back(j);
          b = {i};
        }
      }
      if (a.size() > b.size()) swap(a, b);

      if (a.size() > 2 && !are_connected({a[0]}, {a.back()})) {
        if (are_connected({a[0]}, {b[0]})) return sum(rev(a), b);
        else return sum(a, b);
      }
      if (b.size() > 2 && !are_connected({b[0]}, {b.back()})) {
        if (are_connected({a[0]}, {b[0]})) return sum(rev(a), b);
        else return sum(b, a);
      }

      auto [x, y] = Find(a, b);
      if (x < 0) return b;
      vector<int> ans;
      for(int j = x + 1; j < a.size(); j++) ans.push_back(a[j]);
      for(int j = 0; j <= x; j++) ans.push_back(a[j]);
      for(int j = y; j < b.size(); j++) ans.push_back(b[j]);
      for(int j = 0; j < y; j++) ans.push_back(b[j]);
      return ans;
    }
}

Compilation message

longesttrip.cpp:2:10: fatal error: grader.cpp: No such file or directory
    2 | #include "grader.cpp"
      |          ^~~~~~~~~~~~
compilation terminated.