Submission #1189116

#	Time	Username	Problem	Language	Result	Execution time	Memory
1189116		spacewalker	Robots (IOI13_robots)	C++20	90 / 100	3017 ms	25076 KiB

robots

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

using namespace std;
namespace r = ranges;
namespace v = ranges::views;

vector<pair<int, int>> remove_one_dim(vector<pair<int, int>> toys,
                                      const vector<int> &limits,
                                      int toys_per_bot) {
  int ctoy = 0;
  r::sort(toys);
  // toys are sorted by increasing weight

  priority_queue<pair<int, int>>
      remaining_toys; // toys here are stored in (y, x) order
  for (int weight_limit : limits) {
    while (ctoy < toys.size() && toys[ctoy].first < weight_limit) {
      auto toy = toys[ctoy++];
      remaining_toys.emplace(toy.second, toy.first);
    }
    for (int _i : v::iota(0, toys_per_bot)) {
      if (remaining_toys.empty())
        break;
      auto [y, x] = remaining_toys.top();
      /*cerr << "weight limit " << weight_limit << " to toy " << x << " " << y << endl;*/
      remaining_toys.pop();
    }
  }

  while (ctoy < toys.size()) {
    auto toy = toys[ctoy++];
    remaining_toys.emplace(toy.second, toy.first);
  }

  toys.clear();

  while (!remaining_toys.empty()) {
    auto [y, x] = remaining_toys.top();
    remaining_toys.pop();
    toys.emplace_back(x, y);
  }
  return toys;
}

bool can_put_away(const vector<pair<int, int>> &toys,
                  const vector<int> &weight_limits,
                  const vector<int> &size_limits, int toys_per_bot) {
  auto remaining_toys = remove_one_dim(toys, weight_limits, toys_per_bot);
  vector<pair<int, int>> other_dim;
  for (auto [x, y] : remaining_toys)
    other_dim.emplace_back(y, 1);
  for (int l : size_limits)
    other_dim.emplace_back(l, -1);
  r::sort(other_dim);
  int remaining_count = 0;
  for (auto [y, evt] : other_dim) {
    if (evt == -1) {
      /*cerr << "! robot " << y << endl;*/
      remaining_count = max(remaining_count - toys_per_bot, 0);
    } else {
      /*cerr << "! toy " << y << endl;*/
      remaining_count++;
    }
  }
  /*cerr << remaining_count << " toys remaining " << endl;*/
  return remaining_count == 0;
}

int putaway(int A, int B, int T, int X[], int Y[], int W[], int S[]) {
  vector<int> weight_limits(X, X + A);
  vector<int> size_limits(Y, Y + B);

  r::sort(weight_limits);
  r::sort(size_limits);
  // where is my ranges::to bwaaaaaaaaa
  auto _toys =
      v::iota(0, T) | v::transform([&](int i) { return pair{W[i], S[i]}; });
  vector<pair<int, int>> toys(_toys.begin(), _toys.end());

  if (!can_put_away(toys, weight_limits, size_limits, T))
    return -1;

  int lo = 1, hi = T;
  while (lo < hi) {
    int mid = (lo + hi) / 2;
    /*cerr << "try " << mid << endl;*/
    if (can_put_away(toys, weight_limits, size_limits, mid))
      hi = mid;
    else
      lo = mid + 1;
  }
  return lo;
}

• Subtask 1: 14 / 14
• Subtask 2: 14 / 14
• Subtask 3: 25 / 25
• Subtask 4: 37 / 37
• Subtask 5: 0 / 10