#include <bits/stdc++.h>
#define rep(i,n)for(int i=0;i<(n);i++)
#define INF 1e10
using namespace std;
int ans[400000];
struct Circle{
double x,y,r;
int id;
double bbox[2][2];
Circle(){}
Circle(double x,double y,double r,int id):x(x),y(y),r(r),id(id){
bbox[0][0]=x-r;bbox[0][1]=y-r;
bbox[1][0]=x+r;bbox[1][1]=y+r;
}
};
struct node{
double bbox[2][2];
node*l,*r;
vector<Circle*>circle;
};
double area(double bbox[2][2]){
return (bbox[1][0]-bbox[0][0])*(bbox[1][1]-bbox[0][1]);
}
void init(double bbox[2][2]){
bbox[0][0]=bbox[0][1]=INF;
bbox[1][0]=bbox[1][1]=-INF;
}
void mergeAABB(double bbox[2][2],double bbox2[2][2],double result[2][2]){
rep(i,2){
result[0][i]=min(bbox[0][i],bbox2[0][i]);
result[1][i]=max(bbox[1][i],bbox2[1][i]);
}
}
void createAABB(vector<Circle*>&circle,double result[2][2]){
init(result);
for(auto&c:circle){
mergeAABB(result,c->bbox,result);
}
}
node bvh[400000];
int pointer=0;
#define t_tri 1.
#define t_aabb 1.
inline void setleaf(vector<Circle*>circle,node*n){
n->l=n->r=NULL;
n->circle=circle;
}
struct st{
double cost;
int id;
bool operator<(const st&r)const{
return cost<r.cost;
}
};
//~ st calc(vector<Circle*>&circle,double s){
//~ st res{1,-1};
//~ double box[2][2];init(box);
//~ vector<double>s1(circle.size());
//~ rep(j,circle.size()){
//~ mergeAABB(box,circle[j]->bbox,box);
//~ s1[j]=area(box);
//~ }
//~ init(box);
//~ vector<double>s2(circle.size());
//~ for(int j=circle.size()-1;j>=0;j--){
//~ mergeAABB(box,circle[j]->bbox,box);
//~ s2[j]=area(box);
//~ }
//~ for(int j=0;j+1<circle.size();j++){
//~ double cost=2*t_aabb+(s1[j]/s)*t_tri+(s2[j+1]/s)*t_tri;
//~ if(res.cost>cost){
//~ res.cost=cost;
//~ res.id=j;
//~ }
//~ }
//~ return res;
//~ }
void build(vector<Circle*>&circle,node*n,int depth){
createAABB(circle,n->bbox);
//~ st ans{INF,-1};
//~ double s=area(n->bbox);
if(depth%7==0){
int axis=-1;
double minx=INF,maxx=-INF,miny=INF,maxy=-INF;
rep(i,circle.size()){
minx=min(minx,circle[i]->bbox[0][0]);
maxx=max(maxx,circle[i]->bbox[1][0]);
miny=min(miny,circle[i]->bbox[0][1]);
maxy=max(maxy,circle[i]->bbox[1][1]);
}
//~ rep(i,2){
//~ sort(circle.begin(),circle.end(),[&](auto a,auto b){
//~ if(i==0)return a->x<b->x;
//~ return a->y<b->y;
//~ });
//~ st res=calc(circle,s);
//~ if(res<ans){
//~ ans=res;
//~ axis=i;
//~ }
//~ }
if(maxx-minx>maxy-miny)axis=0;
else axis=1;
sort(circle.begin(),circle.end(),[&](auto a,auto b){
if(axis==0)return a->x<b->x;
return a->y<b->y;
});
}
if(circle.size()<=2){
setleaf(circle,n);
}
else{
n->l=&bvh[pointer++];
n->r=&bvh[pointer++];
int id=circle.size()/2;
vector<Circle*>left(circle.begin(),circle.begin()+id);
vector<Circle*>right(circle.begin()+id,circle.end());
build(left,n->l,depth+1);
build(right,n->r,depth+1);
}
}
inline bool intersect(Circle*c1,Circle*c2){
return pow(c1->x-c2->x,2)+pow(c1->y-c2->y,2)<=pow(c1->r+c2->r,2);
}
inline bool intersect(double bbox1[2][2],double bbox2[2][2]){
if(bbox1[1][0]<bbox2[0][0]||bbox2[1][0]<bbox1[0][0]||bbox1[1][1]<bbox2[0][1]||bbox2[1][1]<bbox1[0][1])return false;
return true;
}
node*intersect(node*n,Circle*c){
if(!intersect(c->bbox,n->bbox))return n;
if(n->l){
auto l=intersect(n->l,c);
auto r=intersect(n->r,c);
if(l==NULL&&r==NULL)return NULL;
if(l==NULL)return r;
if(r==NULL)return l;
n->l=l;n->r=r;
init(n->bbox);
mergeAABB(l->bbox,r->bbox,n->bbox);
return n;
}
else{
auto&circle=n->circle;
vector<Circle*>res;
rep(i,circle.size()){
if(intersect(circle[i],c)){
ans[circle[i]->id]=c->id;
}
else{
res.push_back(circle[i]);
}
}
if(res.empty())return NULL;
circle=res;
createAABB(circle,n->bbox);
return n;
}
}
#define DEBUG
Circle c[400000];
int main(){
#ifdef DEBUG
auto start=chrono::system_clock::now();
#endif
int n;scanf("%d",&n);
vector<Circle*>circle;
rep(i,n){
int x,y,r;scanf("%d%d%d",&x,&y,&r);
c[i]=Circle(x,y,r,i);
}
sort(c,c+n,[](auto a,auto b){
if(a.r==b.r)return a.id<b.id;
return a.r>b.r;
});
rep(i,n){
circle.push_back(&c[i]);
}
node*root=&bvh[pointer++];
build(circle,root,0);
#ifdef DEBUG
auto end=chrono::system_clock::now();
double tim=chrono::duration_cast<chrono::milliseconds>(end-start).count();
printf("build time = %.3lf sec\n",tim/1000);
#endif
memset(ans,-1,sizeof(ans));
rep(i,n){
if(ans[c[i].id]!=-1)continue;
root=intersect(root,&c[i]);
if(root==NULL)break;
}
#ifndef DEBUG
rep(i,n){
if(i)printf(" ");
printf("%d",ans[i]+1);
}
puts("");
#endif
#ifdef DEBUG
auto end2=chrono::system_clock::now();
double tim2=chrono::duration_cast<chrono::milliseconds>(end2-end).count();
printf("intersection time = %.3lf sec\n",tim2/1000);
double tim3=chrono::duration_cast<chrono::milliseconds>(end2-start).count();
printf("total time = %.3lf sec\n",tim3/1000);
#endif
}
Compilation message
circle_selection.cpp: In function 'void build(std::vector<Circle*>&, node*, int)':
circle_selection.cpp:2:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
#define rep(i,n)for(int i=0;i<(n);i++)
^
circle_selection.cpp:88:3: note: in expansion of macro 'rep'
rep(i,circle.size()){
^~~
circle_selection.cpp: In function 'node* intersect(node*, Circle*)':
circle_selection.cpp:2:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
#define rep(i,n)for(int i=0;i<(n);i++)
^
circle_selection.cpp:148:3: note: in expansion of macro 'rep'
rep(i,circle.size()){
^~~
circle_selection.cpp: In function 'int main()':
circle_selection.cpp:170:13: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
int n;scanf("%d",&n);
~~~~~^~~~~~~~~
circle_selection.cpp:173:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
int x,y,r;scanf("%d%d%d",&x,&y,&r);
~~~~~^~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
27 ms |
30072 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
545 ms |
61260 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
28 ms |
61260 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
797 ms |
61464 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
27 ms |
30072 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
27 ms |
30072 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
