Submission #440139

#	Time	Username	Problem	Language	Result	Execution time	Memory
440139		KULIKOLD	Circle selection (APIO18_circle_selection)	C++17	0 / 100	1460 ms	55484 KiB

circle_selection

//#pragma GCC optimize ("O3")
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define endl '\n'
const int DIM = 3E5+7;
const int INF = 1E9;
struct node{
    ll x,y,r,pos;
} A[DIM];
int P[DIM],ans[DIM];
bool mc(const node &a,const node &b){
    if (a.r==b.r){
        return a.pos<b.pos;
    }
    return a.r>b.r;
}
bool can(const node &a,const node &b){
    return (a.r+b.r)*(a.r+b.r)>=(a.x-b.x)*(a.x-b.x)+(a.y-b.y)*(a.y-b.y);
}
int n;
int solve(){


    sort(A+1,A+1+n,mc);
    for(int i = 1;i<=n;++i){
        if (P[i])
            continue;
        P[i] = i;
        ans[A[i].pos] = A[i].pos;
        for(int j = i+1;j<=n;++j)
            if (!P[j] && can(A[i],A[j]))
                P[j] = i,ans[A[j].pos] = A[i].pos;
    }
    for(int i = 1;i<=n;++i)
        cout<<ans[i]<<' ';
    cout<<endl;
    return 1;
}
void solve1(){
    set<pair<ll,ll> > SL,SR;
    sort(A+1,A+1+n,mc);
    for(int i = 1;i<=n;++i){
        SL.insert({A[i].x-A[i].r,i});
        SR.insert({A[i].x+A[i].r,i});
    }

    for(int i = 1;i<=n;++i){
        vector<int> V;
        {
            auto it = SL.lower_bound({A[i].x - A[i].r, 0});

            while (it != SL.end() && it->first <= A[i].x + A[i].r) {
                ans[A[it->second].pos] = A[i].pos;
                V.push_back(it->second);
                it = next(it);
            }
        }
        {
            auto it = SR.upper_bound({A[i].x+A[i].r,INF});
            if (it!=SR.begin()){
                it = prev(it);
                while(it->first>=A[i].x-A[i].r){
                    ans[A[it->second].pos] = A[i].pos;
                    V.push_back(it->second);
                    if (it==SR.begin())
                        break;
                    it = prev(it);
                }
            }
        }
        for(int i:V){
            SL.erase({A[i].x-A[i].r,i});
            SR.erase({A[i].x+A[i].r,i});
        }
    }
    for(int i = 1;i<=n;++i)
        cout<<ans[i]<<' ';
    cout<<endl;
}
int main() {

    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin>>n;
    for(int i = 1;i<=n;++i){
        cin>>A[i].x>>A[i].y>>A[i].r;
        A[i].pos = i;
    }
    if (n<=1)
        solve();
    else
        solve1();
    return 0;
}

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