Submission #741174

#	Time	Username	Problem	Language	Result	Execution time	Memory
741174		speedyArda	Circle selection (APIO18_circle_selection)	C++14	7 / 100	3053 ms	22304 KiB

circle_selection

#include "bits/stdc++.h"
#pragma GCC optimize ("Ofast")
#pragma GCC target("avx,avx2,fma")
#pragma GCC optimization ("unroll-loops")
using namespace std;
const int MAXN = 3e5+5;
vector< pair < pair<int, int>, pair<int, int> > > circles;
vector<int> ans(MAXN, 0);
bool cmp(pair < pair<int, int>, pair<int, int> > a, pair < pair<int, int>, pair<int, int> > b)
{
    if(a.second.first != b.second.first)
        return a.second.first > b.second.first;
    return a.second.second < b.second.second;
}
int main() 
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int n;
    cin >> n;
    for(int i = 0; i < n; i++)
    {
        int x, y, r;
        cin >> x >> y >> r;
        circles.push_back({{x, y}, {r, i}});
    }

    sort(circles.begin(), circles.end(), cmp);
    if(n <= 5e3)
    {
        for(int i = 0; i < n; i++)
        {
            if(ans[circles[i].second.second] != 0)
                continue;
            //cout << circles[i].second.second << "\n";
            ans[circles[i].second.second] = circles[i].second.second + 1;
            for(int a = 0; a < n; a++)
            {
                if(ans[circles[a].second.second] == 0)
                {
                    long double dist = sqrt(pow(abs(circles[i].first.first - circles[a].first.first), 2) + pow(abs(circles[i].first.second - circles[a].first.second), 2));
                    if(dist <= circles[i].second.first + circles[a].second.first)
                        ans[circles[a].second.second] = circles[i].second.second + 1;
                }
            }
        }
    } else 
    {
        multiset< pair<int, int> > elems;
        for(int i = 0; i < n; i++)
        {
            elems.insert({circles[i].first.first, circles[i].second.second});
        }
        for(int i = 0; i < n; i++)
        {
            if(ans[circles[i].second.second] != 0)
                continue;
            auto it = elems.find({circles[i].first.first,  circles[i].second.second});
            auto prev = it;
            vector<int> toerase;
            if(it != elems.begin()) {
                it--;
                while(true)
                {
                    if(circles[i].first.first - (*it).first <= circles[i].second.first  + circles[(*it).second].second.first)
                    {
                        toerase.push_back((*it).second);
                    } else
                        break;
                    if(it == elems.begin())
                        break;
                    it--;
                }
            }
            it = prev;
            while(it != elems.end())
            {
                if(abs(circles[i].first.first - (*it).first) <= circles[i].second.first  + circles[(*it).second].second.first)
                {
                    toerase.push_back((*it).second);
                } else
                    break;
                it++;
            }

            for(int e : toerase)
            {
                ans[circles[e].second.second] = circles[i].second.second + 1;
                elems.erase({circles[e].first.first,  circles[e].second.second});
            }
        }
    }

    for(int i = 0; i < n; i++)
        cout << ans[i] << " ";
    cout << "\n";
}

Compilation message (stderr)

circle_selection.cpp:4: warning: ignoring '#pragma GCC optimization' [-Wunknown-pragmas]
    4 | #pragma GCC optimization ("unroll-loops")
      |

• Subtask 1: 7 / 7
• Subtask 2: 0 / 12
• Subtask 3: 0 / 15
• Subtask 4: 0 / 23
• Subtask 5: 0 / 30
• Subtask 6: 0 / 13