Submission #397263

#	Time	Username	Problem	Language	Result	Execution time	Memory
397263		peuch	Detecting Molecules (IOI16_molecules)	C++17	0 / 100	1 ms	296 KiB

molecules

#include "molecules.h"
#include "molecules.h"
#include<bits/stdc++.h>
using namespace std;

vector<int> getAns(vector<pair<int, int> > aux, int ini, int fim);

std::vector<int> find_subset(int l, int u, std::vector<int> w) {
	int n = w.size();
	
	vector<int> ret;
	vector<pair<int, int> > aux;
	for(int i = 0; i < w.size(); i++)
		aux.push_back(make_pair(w[i], i));
	sort(aux.begin(), aux.end()); 
 	
	vector<int> suf, pref;
	suf.push_back(aux[0].first);
	pref.push_back(aux[n - 1].first);
 	
	for(int i = 1; i < n; i++)
		suf.push_back(suf[suf.size() - 1] + aux[i].first);
 	for(int i = n - 2; i >= 0; i--)
		pref.push_back(pref[pref.size() - 1] + aux[i].first);
 	
	if(suf[n - 1] < l) return ret;
	if(suf[0] > u) return ret;
 	
 	
	if(suf[n - 1] <= u) return getAns(aux, n - 1, n - 1);
 	
	for(int i = 0; i < n; i++){
		if(suf[i] > u) break;
		if(suf[i] >= l) return getAns(aux, i, n + 1);
		int k = lower_bound(pref.begin(), pref.end(), l - suf[i]) - pref.begin();
		if(k == pref.size()) continue;
		if(k + 1 + i + 1 > n) continue;
		if(suf[i] + pref[k] > u) continue;
		if(suf[i] + pref[k] < l) continue;
		k = n - 1 - k;
		if(k <= i) continue;
		return getAns(aux, i, k);
	}
 	
	int k = lower_bound(pref.begin(), pref.end(), l) - pref.begin();
 	
 	if(k == pref.size()) return ret;
 	if(pref[k] > u) return ret;
 	if(pref[k] < l) return ret;
 	k = n - 1 - k;
    return getAns(aux, -1, k);
}

vector<int> getAns(vector<pair<int, int> > aux, int ini, int fim){
	vector<int> ret;
	for(int i = 0; i <= ini; i++)
		ret.push_back(aux[i].second);
	for(int i = aux.size() - 1; i >= fim; i--)
		ret.push_back(aux[i].second);
	sort(ret.begin(), ret.end());
	return ret;
}

Compilation message (stderr)

molecules.cpp: In function 'std::vector<int> find_subset(int, int, std::vector<int>)':
molecules.cpp:13:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   13 |  for(int i = 0; i < w.size(); i++)
      |                 ~~^~~~~~~~~~
molecules.cpp:36:8: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |   if(k == pref.size()) continue;
      |      ~~^~~~~~~~~~~~~~
molecules.cpp:47:8: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   47 |   if(k == pref.size()) return ret;
      |      ~~^~~~~~~~~~~~~~

• Subtask 1: 0 / 9
• Subtask 2: 0 / 10
• Subtask 3: 0 / 12
• Subtask 4: 0 / 15
• Subtask 5: 0 / 23
• Subtask 6: 0 / 31