oj.uz

Submission #77741

# Submission time Handle Problem Language Result Execution time Memory
77741 2018-09-30T06:54:25 Z autumn_eel Circle selection (APIO18_circle_selection) C++14
7 / 100
 2477 ms 48432 KB 
#include <bits/stdc++.h>
#define rep(i,n)for(int i=0;i<(n);i++)
#define INF 1e10
#define EPS (1e-5)
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]+EPS<bbox2[0][0]||bbox2[1][0]+EPS<bbox1[0][0]||bbox1[1][1]+EPS<bbox2[0][1]||bbox2[1][1]+EPS<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/512.,y/512.,r/512.,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:64:3: note: in expansion of macro 'rep'
   rep(j,circle.size()){
   ^~~
circle_selection.cpp:74:18: 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:128:3: note: in expansion of macro 'rep'
   rep(i,circle.size()){
   ^~~
circle_selection.cpp: In function 'int main()':
circle_selection.cpp:145:13: 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:148:18: 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 23800 KB Output is correct
2 Correct 22 ms 23972 KB Output is correct
3 Correct 21 ms 23972 KB Output is correct
4 Correct 22 ms 23972 KB Output is correct
5 Correct 23 ms 24052 KB Output is correct
6 Correct 22 ms 24052 KB Output is correct
7 Correct 34 ms 24052 KB Output is correct
8 Correct 22 ms 24164 KB Output is correct
9 Correct 22 ms 24164 KB Output is correct
10 Correct 25 ms 24164 KB Output is correct
11 Correct 22 ms 24164 KB Output is correct
12 Correct 22 ms 24164 KB Output is correct
13 Correct 25 ms 24164 KB Output is correct
14 Correct 21 ms 24164 KB Output is correct
15 Correct 27 ms 24164 KB Output is correct
16 Correct 25 ms 24164 KB Output is correct
17 Correct 24 ms 24164 KB Output is correct
18 Correct 31 ms 24164 KB Output is correct
19 Correct 37 ms 24416 KB Output is correct
20 Correct 42 ms 24420 KB Output is correct
21 Correct 38 ms 24460 KB Output is correct
22 Correct 42 ms 24604 KB Output is correct
23 Correct 42 ms 24604 KB Output is correct
24 Correct 40 ms 24604 KB Output is correct
25 Correct 42 ms 24604 KB Output is correct
26 Correct 42 ms 24604 KB Output is correct

Subtask #2
0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1486 ms 45636 KB Output is correct
2 Correct 1541 ms 45636 KB Output is correct
3 Correct 1394 ms 45636 KB Output is correct
4 Correct 1472 ms 45712 KB Output is correct
5 Incorrect 1161 ms 45712 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 45712 KB Output is correct
2 Correct 653 ms 45712 KB Output is correct
3 Correct 2368 ms 48308 KB Output is correct
4 Correct 2477 ms 48432 KB Output is correct
5 Incorrect 2245 ms 48432 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #4
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 2424 ms 48432 KB Output is correct
2 Correct 2400 ms 48432 KB Output is correct
3 Correct 1943 ms 48432 KB Output is correct
4 Correct 2421 ms 48432 KB Output is correct
5 Correct 2377 ms 48432 KB Output is correct
6 Incorrect 1929 ms 48432 KB Output isn't correct

Subtask #5
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 22 ms 23800 KB Output is correct
2 Correct 22 ms 23972 KB Output is correct
3 Correct 21 ms 23972 KB Output is correct
4 Correct 22 ms 23972 KB Output is correct
5 Correct 23 ms 24052 KB Output is correct
6 Correct 22 ms 24052 KB Output is correct
7 Correct 34 ms 24052 KB Output is correct
8 Correct 22 ms 24164 KB Output is correct
9 Correct 22 ms 24164 KB Output is correct
10 Correct 25 ms 24164 KB Output is correct
11 Correct 22 ms 24164 KB Output is correct
12 Correct 22 ms 24164 KB Output is correct
13 Correct 25 ms 24164 KB Output is correct
14 Correct 21 ms 24164 KB Output is correct
15 Correct 27 ms 24164 KB Output is correct
16 Correct 25 ms 24164 KB Output is correct
17 Correct 24 ms 24164 KB Output is correct
18 Correct 31 ms 24164 KB Output is correct
19 Correct 37 ms 24416 KB Output is correct
20 Correct 42 ms 24420 KB Output is correct
21 Correct 38 ms 24460 KB Output is correct
22 Correct 42 ms 24604 KB Output is correct
23 Correct 42 ms 24604 KB Output is correct
24 Correct 40 ms 24604 KB Output is correct
25 Correct 42 ms 24604 KB Output is correct
26 Correct 42 ms 24604 KB Output is correct
27 Correct 55 ms 48432 KB Output is correct
28 Correct 54 ms 48432 KB Output is correct
29 Correct 55 ms 48432 KB Output is correct
30 Correct 66 ms 48432 KB Output is correct
31 Correct 64 ms 48432 KB Output is correct
32 Correct 65 ms 48432 KB Output is correct
33 Correct 518 ms 48432 KB Output is correct
34 Correct 494 ms 48432 KB Output is correct
35 Correct 539 ms 48432 KB Output is correct
36 Correct 673 ms 48432 KB Output is correct
37 Correct 638 ms 48432 KB Output is correct
38 Correct 624 ms 48432 KB Output is correct
39 Correct 829 ms 48432 KB Output is correct
40 Correct 792 ms 48432 KB Output is correct
41 Correct 664 ms 48432 KB Output is correct
42 Correct 465 ms 48432 KB Output is correct
43 Incorrect 418 ms 48432 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 23800 KB Output is correct
2 Correct 22 ms 23972 KB Output is correct
3 Correct 21 ms 23972 KB Output is correct
4 Correct 22 ms 23972 KB Output is correct
5 Correct 23 ms 24052 KB Output is correct
6 Correct 22 ms 24052 KB Output is correct
7 Correct 34 ms 24052 KB Output is correct
8 Correct 22 ms 24164 KB Output is correct
9 Correct 22 ms 24164 KB Output is correct
10 Correct 25 ms 24164 KB Output is correct
11 Correct 22 ms 24164 KB Output is correct
12 Correct 22 ms 24164 KB Output is correct
13 Correct 25 ms 24164 KB Output is correct
14 Correct 21 ms 24164 KB Output is correct
15 Correct 27 ms 24164 KB Output is correct
16 Correct 25 ms 24164 KB Output is correct
17 Correct 24 ms 24164 KB Output is correct
18 Correct 31 ms 24164 KB Output is correct
19 Correct 37 ms 24416 KB Output is correct
20 Correct 42 ms 24420 KB Output is correct
21 Correct 38 ms 24460 KB Output is correct
22 Correct 42 ms 24604 KB Output is correct
23 Correct 42 ms 24604 KB Output is correct
24 Correct 40 ms 24604 KB Output is correct
25 Correct 42 ms 24604 KB Output is correct
26 Correct 42 ms 24604 KB Output is correct
27 Correct 1486 ms 45636 KB Output is correct
28 Correct 1541 ms 45636 KB Output is correct
29 Correct 1394 ms 45636 KB Output is correct
30 Correct 1472 ms 45712 KB Output is correct
31 Incorrect 1161 ms 45712 KB Output isn't correct
32 Halted 0 ms 0 KB -