Submission #77745

# Submission time Handle Problem Language Result Execution time Memory
77745 2018-09-30T06:58:43 Z autumn_eel Circle selection (APIO18_circle_selection) C++14
87 / 100
3000 ms 74580 KB
#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.

void setleaf(vector<Circle*>circle,node*n){
	n->l=n->r=NULL;
	n->circle=circle;
}
void build(vector<Circle*>&circle,node*n){
	createAABB(circle,n->bbox);
	double Min=t_tri*circle.size();
	int axis=-1,id=-1;
	double s=area(n->bbox);
	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;
		});
		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)*(j+1)*t_tri+(s2[j+1]/s)*(circle.size()-j-1)*t_tri;
			if(Min>cost){
				Min=cost;
				axis=i;id=j;
			}
		}
	}
	if(axis==-1){
		setleaf(circle,n);
	}
	else{
		sort(circle.begin(),circle.end(),[&](auto a,auto b){
			if(axis==0)return a->x<b->x;
			return a->y<b->y;
		});
		n->l=&bvh[pointer++];
		n->r=&bvh[pointer++];
		vector<Circle*>left(circle.begin(),circle.begin()+id+1);
		vector<Circle*>right(circle.begin()+id+1,circle.end());
		build(left,n->l);
		build(right,n->r);
	}
}
void dfs_bvh(node*n,int depth){
	if(depth==3){
		cout<<"(minx,miny),(maxx,maxy) = "<<"("<<n->bbox[0][0]<<","<<n->bbox[0][1]<<")"<<","<<"("<<n->bbox[1][0]<<","<<n->bbox[1][1]<<")"<<endl;
	}
	if(n->l)dfs_bvh(n->l,depth+1);
	if(n->r)dfs_bvh(n->r,depth+1);
}
bool intersect(Circle*c1,Circle*c2){
	return pow(c1->x-(double)c2->x,2)+pow(c1->y-(double)c2->y,2)<=pow(c1->r+(double)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;
	}
}

Circle c[400000];
int main(){
	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);
	//~ dfs_bvh(root,0);
	memset(ans,-1,sizeof(ans));
	rep(i,n){
		if(ans[c[i].id]!=-1)continue;
		root=intersect(root,&c[i]);
		if(root==NULL)break;
	}
	rep(i,n){
		if(i)printf(" ");
		printf("%d",ans[i]+1);
	}
	puts("");
}

Compilation message

circle_selection.cpp: In function 'void build(std::vector<Circle*>&, node*)':
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:63:3: note: in expansion of macro 'rep'
   rep(j,circle.size()){
   ^~~
circle_selection.cpp:73:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j=0;j+1<circle.size();j++){
               ~~~^~~~~~~~~~~~~~
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:127:3: note: in expansion of macro 'rep'
   rep(i,circle.size()){
   ^~~
circle_selection.cpp: In function 'int main()':
circle_selection.cpp:144:13: 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:147:18: 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 Correct 27 ms 30072 KB Output is correct
2 Correct 27 ms 30072 KB Output is correct
3 Correct 27 ms 30164 KB Output is correct
4 Correct 27 ms 30180 KB Output is correct
5 Correct 27 ms 30180 KB Output is correct
6 Correct 27 ms 30180 KB Output is correct
7 Correct 27 ms 30180 KB Output is correct
8 Correct 28 ms 30256 KB Output is correct
9 Correct 27 ms 30256 KB Output is correct
10 Correct 27 ms 30256 KB Output is correct
11 Correct 34 ms 30256 KB Output is correct
12 Correct 27 ms 30256 KB Output is correct
13 Correct 29 ms 30256 KB Output is correct
14 Correct 27 ms 30256 KB Output is correct
15 Correct 27 ms 30256 KB Output is correct
16 Correct 29 ms 30388 KB Output is correct
17 Correct 29 ms 30388 KB Output is correct
18 Correct 29 ms 30388 KB Output is correct
19 Correct 44 ms 30828 KB Output is correct
20 Correct 47 ms 30828 KB Output is correct
21 Correct 41 ms 30860 KB Output is correct
22 Correct 45 ms 31004 KB Output is correct
23 Correct 60 ms 31004 KB Output is correct
24 Correct 46 ms 31004 KB Output is correct
25 Correct 46 ms 31020 KB Output is correct
26 Correct 46 ms 31020 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1686 ms 61804 KB Output is correct
2 Correct 1573 ms 61804 KB Output is correct
3 Correct 1621 ms 61804 KB Output is correct
4 Correct 1668 ms 61804 KB Output is correct
5 Correct 1495 ms 61804 KB Output is correct
6 Correct 1646 ms 62024 KB Output is correct
7 Correct 1457 ms 62024 KB Output is correct
8 Correct 1491 ms 62024 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 27 ms 62024 KB Output is correct
2 Correct 694 ms 62024 KB Output is correct
3 Correct 2608 ms 63940 KB Output is correct
4 Correct 2675 ms 64036 KB Output is correct
5 Correct 2439 ms 64036 KB Output is correct
6 Correct 1071 ms 64036 KB Output is correct
7 Correct 478 ms 64036 KB Output is correct
8 Correct 96 ms 64036 KB Output is correct
9 Correct 2728 ms 64036 KB Output is correct
10 Correct 2461 ms 64036 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2702 ms 64056 KB Output is correct
2 Correct 2622 ms 64056 KB Output is correct
3 Correct 2284 ms 64056 KB Output is correct
4 Correct 2680 ms 64056 KB Output is correct
5 Correct 2590 ms 64084 KB Output is correct
6 Correct 2182 ms 64084 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 27 ms 30072 KB Output is correct
2 Correct 27 ms 30072 KB Output is correct
3 Correct 27 ms 30164 KB Output is correct
4 Correct 27 ms 30180 KB Output is correct
5 Correct 27 ms 30180 KB Output is correct
6 Correct 27 ms 30180 KB Output is correct
7 Correct 27 ms 30180 KB Output is correct
8 Correct 28 ms 30256 KB Output is correct
9 Correct 27 ms 30256 KB Output is correct
10 Correct 27 ms 30256 KB Output is correct
11 Correct 34 ms 30256 KB Output is correct
12 Correct 27 ms 30256 KB Output is correct
13 Correct 29 ms 30256 KB Output is correct
14 Correct 27 ms 30256 KB Output is correct
15 Correct 27 ms 30256 KB Output is correct
16 Correct 29 ms 30388 KB Output is correct
17 Correct 29 ms 30388 KB Output is correct
18 Correct 29 ms 30388 KB Output is correct
19 Correct 44 ms 30828 KB Output is correct
20 Correct 47 ms 30828 KB Output is correct
21 Correct 41 ms 30860 KB Output is correct
22 Correct 45 ms 31004 KB Output is correct
23 Correct 60 ms 31004 KB Output is correct
24 Correct 46 ms 31004 KB Output is correct
25 Correct 46 ms 31020 KB Output is correct
26 Correct 46 ms 31020 KB Output is correct
27 Correct 60 ms 64084 KB Output is correct
28 Correct 61 ms 64084 KB Output is correct
29 Correct 59 ms 64084 KB Output is correct
30 Correct 67 ms 64084 KB Output is correct
31 Correct 68 ms 64084 KB Output is correct
32 Correct 68 ms 64084 KB Output is correct
33 Correct 513 ms 64084 KB Output is correct
34 Correct 497 ms 64084 KB Output is correct
35 Correct 519 ms 64084 KB Output is correct
36 Correct 635 ms 64084 KB Output is correct
37 Correct 684 ms 64084 KB Output is correct
38 Correct 627 ms 64084 KB Output is correct
39 Correct 793 ms 64084 KB Output is correct
40 Correct 836 ms 64084 KB Output is correct
41 Correct 735 ms 64084 KB Output is correct
42 Correct 520 ms 64084 KB Output is correct
43 Correct 445 ms 64084 KB Output is correct
44 Correct 477 ms 64084 KB Output is correct
45 Correct 458 ms 64084 KB Output is correct
46 Correct 431 ms 64084 KB Output is correct
47 Correct 420 ms 64084 KB Output is correct
48 Correct 460 ms 64084 KB Output is correct
49 Correct 421 ms 64084 KB Output is correct
50 Correct 416 ms 64084 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 27 ms 30072 KB Output is correct
2 Correct 27 ms 30072 KB Output is correct
3 Correct 27 ms 30164 KB Output is correct
4 Correct 27 ms 30180 KB Output is correct
5 Correct 27 ms 30180 KB Output is correct
6 Correct 27 ms 30180 KB Output is correct
7 Correct 27 ms 30180 KB Output is correct
8 Correct 28 ms 30256 KB Output is correct
9 Correct 27 ms 30256 KB Output is correct
10 Correct 27 ms 30256 KB Output is correct
11 Correct 34 ms 30256 KB Output is correct
12 Correct 27 ms 30256 KB Output is correct
13 Correct 29 ms 30256 KB Output is correct
14 Correct 27 ms 30256 KB Output is correct
15 Correct 27 ms 30256 KB Output is correct
16 Correct 29 ms 30388 KB Output is correct
17 Correct 29 ms 30388 KB Output is correct
18 Correct 29 ms 30388 KB Output is correct
19 Correct 44 ms 30828 KB Output is correct
20 Correct 47 ms 30828 KB Output is correct
21 Correct 41 ms 30860 KB Output is correct
22 Correct 45 ms 31004 KB Output is correct
23 Correct 60 ms 31004 KB Output is correct
24 Correct 46 ms 31004 KB Output is correct
25 Correct 46 ms 31020 KB Output is correct
26 Correct 46 ms 31020 KB Output is correct
27 Correct 1686 ms 61804 KB Output is correct
28 Correct 1573 ms 61804 KB Output is correct
29 Correct 1621 ms 61804 KB Output is correct
30 Correct 1668 ms 61804 KB Output is correct
31 Correct 1495 ms 61804 KB Output is correct
32 Correct 1646 ms 62024 KB Output is correct
33 Correct 1457 ms 62024 KB Output is correct
34 Correct 1491 ms 62024 KB Output is correct
35 Correct 27 ms 62024 KB Output is correct
36 Correct 694 ms 62024 KB Output is correct
37 Correct 2608 ms 63940 KB Output is correct
38 Correct 2675 ms 64036 KB Output is correct
39 Correct 2439 ms 64036 KB Output is correct
40 Correct 1071 ms 64036 KB Output is correct
41 Correct 478 ms 64036 KB Output is correct
42 Correct 96 ms 64036 KB Output is correct
43 Correct 2728 ms 64036 KB Output is correct
44 Correct 2461 ms 64036 KB Output is correct
45 Correct 2702 ms 64056 KB Output is correct
46 Correct 2622 ms 64056 KB Output is correct
47 Correct 2284 ms 64056 KB Output is correct
48 Correct 2680 ms 64056 KB Output is correct
49 Correct 2590 ms 64084 KB Output is correct
50 Correct 2182 ms 64084 KB Output is correct
51 Correct 60 ms 64084 KB Output is correct
52 Correct 61 ms 64084 KB Output is correct
53 Correct 59 ms 64084 KB Output is correct
54 Correct 67 ms 64084 KB Output is correct
55 Correct 68 ms 64084 KB Output is correct
56 Correct 68 ms 64084 KB Output is correct
57 Correct 513 ms 64084 KB Output is correct
58 Correct 497 ms 64084 KB Output is correct
59 Correct 519 ms 64084 KB Output is correct
60 Correct 635 ms 64084 KB Output is correct
61 Correct 684 ms 64084 KB Output is correct
62 Correct 627 ms 64084 KB Output is correct
63 Correct 793 ms 64084 KB Output is correct
64 Correct 836 ms 64084 KB Output is correct
65 Correct 735 ms 64084 KB Output is correct
66 Correct 520 ms 64084 KB Output is correct
67 Correct 445 ms 64084 KB Output is correct
68 Correct 477 ms 64084 KB Output is correct
69 Correct 458 ms 64084 KB Output is correct
70 Correct 431 ms 64084 KB Output is correct
71 Correct 420 ms 64084 KB Output is correct
72 Correct 460 ms 64084 KB Output is correct
73 Correct 421 ms 64084 KB Output is correct
74 Correct 416 ms 64084 KB Output is correct
75 Correct 2186 ms 64084 KB Output is correct
76 Correct 2081 ms 64084 KB Output is correct
77 Correct 2052 ms 64084 KB Output is correct
78 Correct 2106 ms 64084 KB Output is correct
79 Correct 2246 ms 64084 KB Output is correct
80 Correct 2232 ms 64084 KB Output is correct
81 Correct 2643 ms 64084 KB Output is correct
82 Correct 2596 ms 64096 KB Output is correct
83 Correct 2628 ms 64096 KB Output is correct
84 Correct 2724 ms 64108 KB Output is correct
85 Correct 2748 ms 64108 KB Output is correct
86 Correct 2757 ms 64108 KB Output is correct
87 Correct 2789 ms 64108 KB Output is correct
88 Execution timed out 3045 ms 74580 KB Time limit exceeded
89 Halted 0 ms 0 KB -