Submission #821345

#	Time	Username	Problem	Language	Result	Execution time	Memory
821345		Kerim	Detecting Molecules (IOI16_molecules)	C++17	100 / 100	36 ms	6332 KiB

molecules

#include "molecules.h"
#include "bits/stdc++.h"
#define ll long long
using namespace std;

vector<int> find_subset(int l, int u, vector<int> w) {
    int n = w.size();
    vector<int> ind(n);
    for (int i = 0; i < n; i++)
        ind[i] = i;
    sort(ind.begin(), ind.end(), [&](int x, int y){
        return (w[x] < w[y]);
    });
    vector<int> answer;
    vector<ll> suf(n+1);
    suf[n] = 0;
    for (int i = n-1; i >= 0; i--)
        suf[i] = suf[i+1] + w[ind[i]];
    ll pref_sum = 0;
    for (int i = 0; i < n; i++){
        if (pref_sum > u)
            break;
        if (pref_sum >= l){
            for (int h = 0; h < i; h++)
                answer.push_back(ind[h]);
            return answer;
        }
        int st = i, en = n-1;
        while (st <= en){
            int mid = (st+en) >> 1;
            ll sum = pref_sum + suf[mid];
            if (l <= sum and  sum <= u){
                for (int h = 0; h < i; h++)
                    answer.push_back(ind[h]);
                for (int h = mid; h < n; h++)
                    answer.push_back(ind[h]);
                return answer;
            }
            if (sum > u) 
                st = mid + 1;
            else
                en = mid - 1;
        }
        pref_sum += w[ind[i]];
    }
    return vector<int>{};
}

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