Submission #256409

#	Time	Username	Problem	Language	Result	Execution time	Memory
256409		SpeedOfMagic	Detecting Molecules (IOI16_molecules)	C++17	100 / 100	66 ms	6252 KiB

molecules

#include <bits/stdc++.h>

#include "molecules.h"


using ll = long long;

using namespace std;

std::vector<int> find_subset(int l, int u, std::vector<int> w) {
	vector<pair<int, int>> ww;
	for (size_t i = 0; i < w.size(); ++i)
		ww.push_back({w[i], i});
	sort(ww.begin(), ww.end());
	ll cur = 0;
	vector<int> result;
	for (int i = 0; i < ww.size(); ++i) {
		if (cur + ww[i].first < l) {
			result.push_back(ww[i].second);
			cur += ww[i].first;
		} else if (cur + ww[i].first <= u) {
			result.push_back(ww[i].second);
			cur += ww[i].first;
			break;
		} else {
			break;
		}
	}
	if (cur >= l) {
		sort(result.begin(), result.end());
		return result;
	} else {
		int j = 0;
		for (int i = ww.size() - 1; i >= result.size() && j < result.size(); --i) {
			cur -= w[result[j]];
			cur += ww[i].first;
			result[j] = ww[i].second;
			++j;
			if (cur >= l) {
				assert(cur <= u);
				sort(result.begin(), result.end());
				return result;
			}
		}
		return {};
	}
}

Compilation message (stderr)

molecules.cpp: In function 'std::vector<int> find_subset(int, int, std::vector<int>)':
molecules.cpp:17:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < ww.size(); ++i) {
                  ~~^~~~~~~~~~~
molecules.cpp:34:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i = ww.size() - 1; i >= result.size() && j < result.size(); --i) {
                               ~~^~~~~~~~~~~~~~~~
molecules.cpp:34:55: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i = ww.size() - 1; i >= result.size() && j < result.size(); --i) {
                                                     ~~^~~~~~~~~~~~~~~

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