Submission #875492

#	Time	Username	Problem	Language	Result	Execution time	Memory
875492		AverageAmogusEnjoyer	Detecting Molecules (IOI16_molecules)	C++17	100 / 100	43 ms	10324 KiB

molecules

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
template<class T> bool cmin(T &i, T j) { return i > j ? i=j,1:0; }
template<class T> bool cmax(T &i, T j) { return i < j ? i=j,1:0; }
vector<int> find_subset(int l, int u, vector<int> w) {
    int n = int(w.size());
    vector<pair<ll,int>> v(n);
    for (int i=0;i<n;i++) {
        v[i]=make_pair(w[i],i);
    }
    sort(v.begin(),v.end());
    vector<ll> p1(n),p2(n);
    p1[0]=v[0].first;
    p2[n-1]=v[n-1].first;
    vector<int> res;
    for (int i=1;i<n;i++) {
        p1[i]=p1[i-1]+v[i].first;
    }
    for (int i=n-2;i>=0;--i) {
        p2[i]=p2[i+1]+v[i].first;
    }
    for (int i=0;i<n;i++) {
        if (p1[i]>=l&&p1[i]<=u) {
            for (int k=0;k<=i;k++) {
                res.push_back(v[k].second);
            }
            return res;
        }
    }
    for (int i=0;i<n;i++) {
        if (p2[i]>=l&&p2[i]<=u) {
            for (int k=n-1;k>=i;k--) {
                res.push_back(v[k].second);
            }
            return res;
        }
    }
    for (int i=0;i<n;i++) {
        int pos = lower_bound(p1.begin(),p1.end(),l-p2[i])-p1.begin();
        if (pos==n||p2[i]+p1[pos]>u||pos>=i) {
            continue;
        }
        for (int j=0;j<=pos;j++) {
            res.push_back(v[j].second);
        }
        for (int j=i;j<n;j++) {
            res.push_back(v[j].second);
        }
        return res;
    }
    return res;
}
/*
 * Say I 'overbuilt' and got sum K > U for some prefix [0...i] and suffix [j...n-1]
 * Now I want to 'add and subtract' some pair of numbers: that is, add a number which 
 * wasn't in previously and subtract an old one. 
*/

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