Submission #1087892

#	Time	Username	Problem	Language	Result	Execution time	Memory
1087892		alexander707070	Circle selection (APIO18_circle_selection)	C++14	0 / 100	652 ms	57992 KiB

circle_selection

#include<bits/stdc++.h>
#define MAXN 600007
using namespace std;

int n,par[MAXN],cnt;
long long x[MAXN],y[MAXN],r[MAXN];
pair<int,int> p[MAXN];

map<int,int> mp;
vector<int> w;

int tree[4*MAXN];

void update(int v,int l,int r,int ll,int rr,int val){
    if(ll>rr)return;
    if(l==ll and r==rr){
        tree[v]=val;
    }else{
        int tt=(l+r)/2;

        if(tree[v]!=0)tree[2*v]=tree[2*v+1]=tree[v];
        update(2*v,l,tt,ll,min(tt,rr),val);
        update(2*v+1,tt+1,r,max(tt+1,ll),rr,val);
    }
}

int getpos(int v,int l,int r,int pos){
    if(l==r)return tree[v];

    int tt=(l+r)/2;
    if(tree[v]!=0)tree[2*v]=tree[2*v+1]=tree[v];

    if(pos<=tt)return getpos(2*v,l,tt,pos);
    return getpos(2*v+1,tt+1,r,pos);
}

int main(){

    cin>>n;
    for(int i=1;i<=n;i++){
        cin>>x[i]>>y[i]>>r[i];

        w.push_back(x[i]-r[i]);
        w.push_back(x[i]+r[i]);

        p[i]={r[i],-i};
    }

    sort(w.begin(),w.end());

    for(int i=0;i<w.size();i++){
        if(i==0 or w[i]!=w[i-1])cnt++;
        mp[w[i]]=cnt;
    }

    sort(p+1,p+n+1);

    for(int i=n;i>=1;i--){
        int curr=-p[i].second;
        
        int e=getpos(1,1,cnt,mp[x[curr]-r[curr]]);
        if(e!=0){
            par[curr]=e; continue;
        }

        e=getpos(1,1,cnt,mp[x[curr]+r[curr]]);
        if(e!=0){
            par[curr]=e; continue;
        }

        par[curr]=curr;
        update(1,1,cnt,mp[x[curr]-r[curr]],mp[x[curr]+r[curr]],curr);
    }

    for(int i=1;i<=n;i++){
        cout<<par[i]<<" ";
    }
    cout<<"\n";

    return 0;
}

Compilation message (stderr)

circle_selection.cpp: In function 'int main()':
circle_selection.cpp:51:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   51 |     for(int i=0;i<w.size();i++){
      |                 ~^~~~~~~~~

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