Submission #102759

#	Time	Username	Problem	Language	Result	Execution time	Memory
102759		wxh010910	Rail (IOI14_rail)	C++17	100 / 100	98 ms	760 KiB

rail

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

using namespace std;

void findLocation(int N, int first, int location[], int stype[]) {
  location[0] = first;
  stype[0] = 1;
  vector<int> dist0(N);
  for (int i = 1; i < N; ++i) {
    dist0[i] = getDistance(0, i);
  }
  int p = 1;
  for (int i = 2; i < N; ++i) {
    if (dist0[p] > dist0[i]) {
      p = i;
    }
  }
  location[p] = first + dist0[p];
  stype[p] = 2;
  vector<int> distp(N);
  vector<int> left;
  vector<int> right;
  for (int i = 1; i < N; ++i) {
    if (i != p) {
      distp[i] = getDistance(p, i);
      if (dist0[i] == distp[i] + dist0[p] && distp[i] <= dist0[p]) {
        location[i] = location[p] - distp[i];
        stype[i] = 1;
      } else {
        if (dist0[i] == distp[i] + dist0[p]) {
          left.push_back(i);
        } else {
          right.push_back(i);
        }
      }
    }
  }
  {
    sort(left.begin(), left.end(), [&](int a, int b) {
      return distp[a] < distp[b];
    });
    vector<int> down;
    down.push_back(0);
    for (auto i : left) {
      int foo = location[p] - distp[i];
      int bar = location[down.back()] + getDistance(down.back(), i);
      int near = -1;
      for (auto j : down) {
        if (location[j] <= bar) {
          near = j;
          break;
        }
      }
      if (location[near] - foo == bar - location[near]) {
        location[i] = bar;
        stype[i] = 2;
      } else {
        location[i] = foo;
        stype[i] = 1;
        down.push_back(i);
      }
    }
  }
  {
    sort(right.begin(), right.end(), [&](int a, int b) {
      return dist0[a] < dist0[b];
    });
    vector<int> up;
    up.push_back(p);
    for (auto i : right) {
      int foo = location[0] + dist0[i];
      int bar = location[up.back()] - getDistance(up.back(), i);
      int near = -1;
      for (auto j : up) {
        if (location[j] >= bar) {
          near = j;
          break;
        }
      }
      if (foo - location[near] == location[near] - bar) {
        location[i] = bar;
        stype[i] = 1;
      } else {
        location[i] = foo;
        stype[i] = 2;
        up.push_back(i);
      }
    }
  }
}

• Subtask 1: 8 / 8
• Subtask 2: 22 / 22
• Subtask 3: 26 / 26
• Subtask 4: 44 / 44