oj.uz

Submission #77742

# Submission time Handle Problem Language Result Execution time Memory
77742 2018-09-30T06:56:11 Z autumn_eel Circle selection (APIO18_circle_selection) C++14
7 / 100
 2464 ms 48424 KB 
#include <bits/stdc++.h>
#define rep(i,n)for(int i=0;i<(n);i++)
#define INF 4e9
#define EPS (1e-3)
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 21 ms 23968 KB Output is correct
3 Correct 22 ms 23968 KB Output is correct
4 Correct 23 ms 23968 KB Output is correct
5 Correct 22 ms 23968 KB Output is correct
6 Correct 27 ms 23968 KB Output is correct
7 Correct 22 ms 23976 KB Output is correct
8 Correct 22 ms 24144 KB Output is correct
9 Correct 23 ms 24144 KB Output is correct
10 Correct 22 ms 24144 KB Output is correct
11 Correct 28 ms 24144 KB Output is correct
12 Correct 22 ms 24144 KB Output is correct
13 Correct 24 ms 24144 KB Output is correct
14 Correct 28 ms 24144 KB Output is correct
15 Correct 25 ms 24144 KB Output is correct
16 Correct 32 ms 24160 KB Output is correct
17 Correct 33 ms 24160 KB Output is correct
18 Correct 24 ms 24172 KB Output is correct
19 Correct 38 ms 24428 KB Output is correct
20 Correct 37 ms 24428 KB Output is correct
21 Correct 36 ms 24444 KB Output is correct
22 Correct 40 ms 24444 KB Output is correct
23 Correct 44 ms 24588 KB Output is correct
24 Correct 40 ms 24588 KB Output is correct
25 Correct 42 ms 24588 KB Output is correct
26 Correct 42 ms 24588 KB Output is correct

Subtask #2
0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1520 ms 45684 KB Output is correct
2 Correct 1490 ms 45684 KB Output is correct
3 Correct 1462 ms 45684 KB Output is correct
4 Correct 1504 ms 45684 KB Output is correct
5 Incorrect 1097 ms 45684 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 22 ms 45684 KB Output is correct
2 Correct 648 ms 45684 KB Output is correct
3 Correct 2464 ms 48424 KB Output is correct
4 Correct 2412 ms 48424 KB Output is correct
5 Incorrect 2209 ms 48424 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #4
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 2375 ms 48424 KB Output is correct
2 Correct 2334 ms 48424 KB Output is correct
3 Correct 1981 ms 48424 KB Output is correct
4 Correct 2341 ms 48424 KB Output is correct
5 Correct 2409 ms 48424 KB Output is correct
6 Incorrect 1886 ms 48424 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 21 ms 23968 KB Output is correct
3 Correct 22 ms 23968 KB Output is correct
4 Correct 23 ms 23968 KB Output is correct
5 Correct 22 ms 23968 KB Output is correct
6 Correct 27 ms 23968 KB Output is correct
7 Correct 22 ms 23976 KB Output is correct
8 Correct 22 ms 24144 KB Output is correct
9 Correct 23 ms 24144 KB Output is correct
10 Correct 22 ms 24144 KB Output is correct
11 Correct 28 ms 24144 KB Output is correct
12 Correct 22 ms 24144 KB Output is correct
13 Correct 24 ms 24144 KB Output is correct
14 Correct 28 ms 24144 KB Output is correct
15 Correct 25 ms 24144 KB Output is correct
16 Correct 32 ms 24160 KB Output is correct
17 Correct 33 ms 24160 KB Output is correct
18 Correct 24 ms 24172 KB Output is correct
19 Correct 38 ms 24428 KB Output is correct
20 Correct 37 ms 24428 KB Output is correct
21 Correct 36 ms 24444 KB Output is correct
22 Correct 40 ms 24444 KB Output is correct
23 Correct 44 ms 24588 KB Output is correct
24 Correct 40 ms 24588 KB Output is correct
25 Correct 42 ms 24588 KB Output is correct
26 Correct 42 ms 24588 KB Output is correct
27 Correct 55 ms 48424 KB Output is correct
28 Correct 54 ms 48424 KB Output is correct
29 Correct 54 ms 48424 KB Output is correct
30 Correct 66 ms 48424 KB Output is correct
31 Correct 65 ms 48424 KB Output is correct
32 Correct 67 ms 48424 KB Output is correct
33 Correct 507 ms 48424 KB Output is correct
34 Correct 488 ms 48424 KB Output is correct
35 Correct 507 ms 48424 KB Output is correct
36 Correct 641 ms 48424 KB Output is correct
37 Correct 611 ms 48424 KB Output is correct
38 Correct 647 ms 48424 KB Output is correct
39 Correct 789 ms 48424 KB Output is correct
40 Correct 804 ms 48424 KB Output is correct
41 Correct 699 ms 48424 KB Output is correct
42 Correct 472 ms 48424 KB Output is correct
43 Incorrect 419 ms 48424 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 21 ms 23968 KB Output is correct
3 Correct 22 ms 23968 KB Output is correct
4 Correct 23 ms 23968 KB Output is correct
5 Correct 22 ms 23968 KB Output is correct
6 Correct 27 ms 23968 KB Output is correct
7 Correct 22 ms 23976 KB Output is correct
8 Correct 22 ms 24144 KB Output is correct
9 Correct 23 ms 24144 KB Output is correct
10 Correct 22 ms 24144 KB Output is correct
11 Correct 28 ms 24144 KB Output is correct
12 Correct 22 ms 24144 KB Output is correct
13 Correct 24 ms 24144 KB Output is correct
14 Correct 28 ms 24144 KB Output is correct
15 Correct 25 ms 24144 KB Output is correct
16 Correct 32 ms 24160 KB Output is correct
17 Correct 33 ms 24160 KB Output is correct
18 Correct 24 ms 24172 KB Output is correct
19 Correct 38 ms 24428 KB Output is correct
20 Correct 37 ms 24428 KB Output is correct
21 Correct 36 ms 24444 KB Output is correct
22 Correct 40 ms 24444 KB Output is correct
23 Correct 44 ms 24588 KB Output is correct
24 Correct 40 ms 24588 KB Output is correct
25 Correct 42 ms 24588 KB Output is correct
26 Correct 42 ms 24588 KB Output is correct
27 Correct 1520 ms 45684 KB Output is correct
28 Correct 1490 ms 45684 KB Output is correct
29 Correct 1462 ms 45684 KB Output is correct
30 Correct 1504 ms 45684 KB Output is correct
31 Incorrect 1097 ms 45684 KB Output isn't correct
32 Halted 0 ms 0 KB -