Submission #392187

#	Time	Username	Problem	Language	Result	Execution time	Memory
392187		Hegdahl	Detecting Molecules (IOI16_molecules)	C++17	100 / 100	57 ms	4792 KiB

molecules

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

using namespace std;
using ll = long long;

vector<int> find_subset(int _l, int _u, vector<int> w) {
  ll l = _l, u = _u;
  int n = w.size();

  ll mn = 1LL<<60;
  for (int v : w)
    mn = min(mn, (ll)v);

  if (mn > u) return {};

  vector<int> idxs(n);
  iota(idxs.begin(), idxs.end(), 0);
  sort(idxs.begin(), idxs.end(), [&](int i, int j){ return w[i] < w[j]; });

  ll s = 0;

  vector<int> ans;

  for (int _i = 0; _i < n; ++_i) {
    int i = idxs[_i];

    if (s + w[i] > u) {
      break;
    }

    s += w[i];
    ans.push_back(i);

    if (s >= l) return ans;
  }

  int i = 0;
  int d = max(ans.size(), n-ans.size());

  while (i+d < n && i < ans.size()) {
    s -= w[ans[i]];
    ans[i] = idxs[i+d];
    s += w[ans[i]];
    ++i;
    if (s >= l) return ans;
  }

  return {};
}

Compilation message (stderr)

molecules.cpp: In function 'std::vector<int> find_subset(int, int, std::vector<int>)':
molecules.cpp:41:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   41 |   while (i+d < n && i < ans.size()) {
      |                     ~~^~~~~~~~~~~~

• Subtask 1: 9 / 9
• Subtask 2: 10 / 10
• Subtask 3: 12 / 12
• Subtask 4: 15 / 15
• Subtask 5: 23 / 23
• Subtask 6: 31 / 31