oj.uz

Submission #77744

# Submission time Handle Problem Language Result Execution time Memory
77744 2018-09-30T06:57:53 Z autumn_eel Circle selection (APIO18_circle_selection) C++14
7 / 100
 2438 ms 48464 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{
	float x,y,r;
	int id;
	float bbox[2][2];
	Circle(){}
	Circle(float x,float y,float 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{
	float bbox[2][2];
	node*l,*r;
	vector<Circle*>circle;
};
float area(float bbox[2][2]){
	return (bbox[1][0]-bbox[0][0])*(bbox[1][1]-bbox[0][1]);
}
void init(float bbox[2][2]){
	bbox[0][0]=bbox[0][1]=INF;
	bbox[1][0]=bbox[1][1]=-INF;
}
void mergeAABB(float bbox[2][2],float bbox2[2][2],float 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,float 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);
	float Min=t_tri*circle.size();
	int axis=-1,id=-1;
	float 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;
		});
		float box[2][2];init(box);
		vector<float>s1(circle.size());
		rep(j,circle.size()){
			mergeAABB(box,circle[j]->bbox,box);
			s1[j]=area(box);
		}
		init(box);
		vector<float>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++){
			float 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(float bbox1[2][2],float 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);
             ~~~~~^~~~~~~~~~~~~~~~~~~

Subtask #1
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 22 ms 23928 KB Output is correct
2 Correct 22 ms 24012 KB Output is correct
3 Correct 22 ms 24012 KB Output is correct
4 Correct 22 ms 24012 KB Output is correct
5 Correct 21 ms 24012 KB Output is correct
6 Correct 22 ms 24012 KB Output is correct
7 Correct 22 ms 24012 KB Output is correct
8 Correct 22 ms 24012 KB Output is correct
9 Correct 22 ms 24128 KB Output is correct
10 Correct 22 ms 24128 KB Output is correct
11 Correct 22 ms 24128 KB Output is correct
12 Correct 22 ms 24128 KB Output is correct
13 Correct 21 ms 24128 KB Output is correct
14 Correct 22 ms 24128 KB Output is correct
15 Correct 22 ms 24128 KB Output is correct
16 Correct 24 ms 24128 KB Output is correct
17 Correct 24 ms 24128 KB Output is correct
18 Correct 23 ms 24128 KB Output is correct
19 Correct 35 ms 24416 KB Output is correct
20 Correct 35 ms 24416 KB Output is correct
21 Correct 35 ms 24432 KB Output is correct
22 Correct 39 ms 24448 KB Output is correct
23 Correct 39 ms 24464 KB Output is correct
24 Correct 40 ms 24464 KB Output is correct
25 Correct 41 ms 24500 KB Output is correct
26 Correct 53 ms 24500 KB Output is correct

Subtask #2
0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1409 ms 45636 KB Output is correct
2 Correct 1479 ms 45636 KB Output is correct
3 Correct 1564 ms 45636 KB Output is correct
4 Correct 1440 ms 45636 KB Output is correct
5 Incorrect 1201 ms 45636 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 23 ms 45636 KB Output is correct
2 Correct 640 ms 45636 KB Output is correct
3 Correct 2438 ms 48464 KB Output is correct
4 Correct 2422 ms 48464 KB Output is correct
5 Incorrect 2177 ms 48464 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #4
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 2322 ms 48464 KB Output is correct
2 Correct 2419 ms 48464 KB Output is correct
3 Correct 1980 ms 48464 KB Output is correct
4 Correct 2342 ms 48464 KB Output is correct
5 Correct 2384 ms 48464 KB Output is correct
6 Incorrect 1888 ms 48464 KB Output isn't correct

Subtask #5
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 22 ms 23928 KB Output is correct
2 Correct 22 ms 24012 KB Output is correct
3 Correct 22 ms 24012 KB Output is correct
4 Correct 22 ms 24012 KB Output is correct
5 Correct 21 ms 24012 KB Output is correct
6 Correct 22 ms 24012 KB Output is correct
7 Correct 22 ms 24012 KB Output is correct
8 Correct 22 ms 24012 KB Output is correct
9 Correct 22 ms 24128 KB Output is correct
10 Correct 22 ms 24128 KB Output is correct
11 Correct 22 ms 24128 KB Output is correct
12 Correct 22 ms 24128 KB Output is correct
13 Correct 21 ms 24128 KB Output is correct
14 Correct 22 ms 24128 KB Output is correct
15 Correct 22 ms 24128 KB Output is correct
16 Correct 24 ms 24128 KB Output is correct
17 Correct 24 ms 24128 KB Output is correct
18 Correct 23 ms 24128 KB Output is correct
19 Correct 35 ms 24416 KB Output is correct
20 Correct 35 ms 24416 KB Output is correct
21 Correct 35 ms 24432 KB Output is correct
22 Correct 39 ms 24448 KB Output is correct
23 Correct 39 ms 24464 KB Output is correct
24 Correct 40 ms 24464 KB Output is correct
25 Correct 41 ms 24500 KB Output is correct
26 Correct 53 ms 24500 KB Output is correct
27 Correct 55 ms 48464 KB Output is correct
28 Correct 58 ms 48464 KB Output is correct
29 Correct 55 ms 48464 KB Output is correct
30 Correct 79 ms 48464 KB Output is correct
31 Correct 67 ms 48464 KB Output is correct
32 Correct 67 ms 48464 KB Output is correct
33 Correct 548 ms 48464 KB Output is correct
34 Correct 497 ms 48464 KB Output is correct
35 Correct 509 ms 48464 KB Output is correct
36 Correct 622 ms 48464 KB Output is correct
37 Correct 644 ms 48464 KB Output is correct
38 Correct 637 ms 48464 KB Output is correct
39 Correct 833 ms 48464 KB Output is correct
40 Correct 816 ms 48464 KB Output is correct
41 Correct 670 ms 48464 KB Output is correct
42 Correct 478 ms 48464 KB Output is correct
43 Incorrect 530 ms 48464 KB Output isn't correct
44 Halted 0 ms 0 KB -

Subtask #6
0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 22 ms 23928 KB Output is correct
2 Correct 22 ms 24012 KB Output is correct
3 Correct 22 ms 24012 KB Output is correct
4 Correct 22 ms 24012 KB Output is correct
5 Correct 21 ms 24012 KB Output is correct
6 Correct 22 ms 24012 KB Output is correct
7 Correct 22 ms 24012 KB Output is correct
8 Correct 22 ms 24012 KB Output is correct
9 Correct 22 ms 24128 KB Output is correct
10 Correct 22 ms 24128 KB Output is correct
11 Correct 22 ms 24128 KB Output is correct
12 Correct 22 ms 24128 KB Output is correct
13 Correct 21 ms 24128 KB Output is correct
14 Correct 22 ms 24128 KB Output is correct
15 Correct 22 ms 24128 KB Output is correct
16 Correct 24 ms 24128 KB Output is correct
17 Correct 24 ms 24128 KB Output is correct
18 Correct 23 ms 24128 KB Output is correct
19 Correct 35 ms 24416 KB Output is correct
20 Correct 35 ms 24416 KB Output is correct
21 Correct 35 ms 24432 KB Output is correct
22 Correct 39 ms 24448 KB Output is correct
23 Correct 39 ms 24464 KB Output is correct
24 Correct 40 ms 24464 KB Output is correct
25 Correct 41 ms 24500 KB Output is correct
26 Correct 53 ms 24500 KB Output is correct
27 Correct 1409 ms 45636 KB Output is correct
28 Correct 1479 ms 45636 KB Output is correct
29 Correct 1564 ms 45636 KB Output is correct
30 Correct 1440 ms 45636 KB Output is correct
31 Incorrect 1201 ms 45636 KB Output isn't correct
32 Halted 0 ms 0 KB -