Submission #1012993

#	Time	Username	Problem	Language	Result	Execution time	Memory
1012993		aufan	Detecting Molecules (IOI16_molecules)	C++17	100 / 100	35 ms	6340 KiB

molecules

#include "molecules.h"
#include <bits/stdc++.h>

using namespace std;
vector<int> find_subset(int l, int u, vector<int> w) {
    long long sum = 0;
    vector<pair<int, int>> v;
    int n = w.size();
    for (int i = 0; i < n; i++) v.push_back(make_pair(w[i], i));
    sort(v.begin(), v.end());
    int idx;
    for (int i = 0; i < n; i++) {
        sum += v[i].first;
        if (sum >= l) {
            idx = i;
            break;
        }
    }
    vector<int> ans;
    if (sum < l) {
        return ans;
    }
    if (sum <= u) {
        for (int i = 0; i <= idx; i++) {
            ans.push_back(v[i].second);
        }
        return ans;
    } else {
        sum -= v[idx].first;
        int p = n - 1;
        for (int i = idx - 1; i >= 0; i--) {
            sum -= v[i].first;
            sum += v[p].first;
            if (sum >= l) {
                for (int j = 0; j < i; j++) {
                    ans.push_back(v[j].second);
                }
                for (int j = p; j < n; j++) {
                    ans.push_back(v[j].second);
                }
                return ans;
            }
            p--;
        }
        return ans;
    }
}

Compilation message (stderr)

molecules.cpp: In function 'std::vector<int> find_subset(int, int, std::vector<int>)':
molecules.cpp:11:9: warning: 'idx' may be used uninitialized in this function [-Wmaybe-uninitialized]
   11 |     int idx;
      |         ^~~

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