Submission #651359

#	Time	Username	Problem	Language	Result	Execution time	Memory
651359		pauloamed	Detecting Molecules (IOI16_molecules)	C++14	0 / 100	1 ms	212 KiB

molecules

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

#define ll long long

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

  vector<pair<int,int>> W;
  for(int i = 0; i < n; ++i){
    W.push_back({w[i], i});
  }
  sort(W.begin(), W.end());

  ll pref[n], suf[n];
  for(int i = 0; i < n; ++i){
    pref[i] = W[i].first;
    if(i) pref[i] += pref[i - 1];
  }

  for(int i = n - 1; i >= 0; --i){
    suf[i] = W[i].first;
    if(i < n - 1) suf[i] += suf[i + 1];
  }

  if(pref[0] > u) return {};
  if(suf[0] < l) return {};
  if(pref[0] >= l) return {0};

  int start = -1;
  for(int i = 0; i < n; ++i){
    if(pref[i] > l){
      start = i - 1;
      break;
    }
  }

  int r = n - 1;
  while(start >= 0){
    int suf_pts = (r + 1 == n)? 0 : suf[r + 1];

    int x = pref[start] + suf_pts;
    if(x >= l && x <= u){
      vector<int> ans;
      for(int i = 0; i <= start; ++i) 
        ans.push_back(W[i].second);

      for(int i = r + 1; i < n; ++i) 
        ans.push_back(W[i].second);

      return ans;
    }
    start--;
    r--;
  }

  int suf_pts = (r + 1 == n)? 0 : suf[r + 1];
  if(suf_pts >= l && suf_pts <= u){
    vector<int> ans;
    for(int i = r + 1; i < n; ++i) 
      ans.push_back(W[i].second);

    return ans;
  }

  return {};
}

// int32_t main(){
//   auto ret = find_subset(15, 17, {6,8,8,7});
//   for(auto x : ret) cout << x << " ";
//   cout << "\n";

//   ret = find_subset(14, 15, {5, 5, 6, 6});
//   for(auto x : ret) cout << x << " ";
//   cout << "\n";

//   ret = find_subset(10, 20, {15, 17, 16, 18});
//   for(auto x : ret) cout << x << " ";
//   cout << "\n";
// }

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