Submission #299391

#	Time	Username	Problem	Language	Result	Execution time	Memory
299391		c4ts0up	Detecting Molecules (IOI16_molecules)	C++17	100 / 100	73 ms	6884 KiB

molecules

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

#define pb push_back
#define ff first
#define ss second
typedef long long ll;

ll n;
vector <pair <ll,int> > arr;
vector <ll> ps;
vector <int> res;

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

    // pasamos los valores al arreglo global
    for (int i=0; i<n; i++) arr.pb({(ll)(w[i]), (i)});
    // ordenamos el arreglo
    sort(arr.begin(), arr.end());
    // hacemos el prefix sum
    ps.resize(n+1);
    ps[0] = 0LL;
    for (int i=0; i<n; i++) ps[i+1] = ps[i] + arr[i].ff;

    //cout << "ps: ";
    //for (int x : ps) cout << x << ", ";
    //cout << endl;

    // fuerza bruta
    int bajo, alto;
    bool flag = false;

    for (int i=0; i<n && !flag; i++) {
        int lb = i, ub = n, mid;
        while (lb <= ub) {
            mid = (lb+ub)/2;
            if (ps[mid]-ps[i] < l) lb = mid+1;
            else ub = mid-1;
        }

        //cout << i << " : " << "lb = " << lb << ", ub = " << ub << ", mid = " << mid << endl;
        
        if (i <= lb && lb <= n && l <= ps[lb]-ps[i] && ps[lb]-ps[i] <= u) {
            bajo = i;
            alto = lb-1;
            flag = true;
        }
        if (i <= ub && ub <= n && l <= ps[ub]-ps[i] && ps[ub]-ps[i] <= u) {
            bajo = i;
            alto = ub-1;
            flag = true;
        }
    }

    if (flag) {
        for (int idx=bajo; idx<=alto; idx++) res.pb(arr[idx].ss);
    }

    return res;
}

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