Submission #3589

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
3589	2013-08-31T06:45:40 Z	imsifile	Jogging (kriii1_J)	C++	0 / 1	1000 ms	7524 KB

J

// 1/tanx = x/y - a*1/y (각도가 높아질수록 감소)
#include<stdio.h>
#include<algorithm>
#include<cmath>
#include<set>
using namespace std;

struct lin {
	double a, b;
	bool operator< (const lin& c) const {
		if(a!=c.a)return a<c.a;
		return b<c.b;
	}
}ba[111111], im, dl[111111];

int dir(lin p, lin q, lin r){
	double t = p.a*q.b + q.a*r.b + r.a*p.b - p.b*q.a - q.b*r.a - r.b*p.a;
	if(t>0)return 1;
	if(t<0)return -1;
	return 0; // 기울기가 1이 되어야 함
}

int n, m, cn;
double xs[111111], dap[111111];
set<lin> conv;
set<lin>::iterator it, a, b, lm;

int main(){
	int i, j, k;
	scanf("%d%d", &n, &m);
	for(i=0; i<n; i++)scanf("%lf%lf", &ba[i].a, &ba[i].b);
	sort(ba, ba+n);
	for(i=0; i<m; i++)scanf("%lf", &xs[i]);
	for(i=m-1, j=n-1; i>=0; i--){
		while(j>=0){
			if(xs[i]>=ba[j].a)break;
			im.a=-1/ba[j].b, im.b=ba[j].a/ba[j].b;
			if(conv.empty()){
				conv.insert(im), j--;
				continue;
			}
			cn=0;
			it=conv.lower_bound(im), lm=conv.begin();
			if(it!=lm){
				a=b=it, a--, b--;
				if(a!=lm){
					b--;
					while(dir(*b,*a,im)!=1){
						dl[cn++]=*a;
						a=b, b--;
						if(a==lm)break;
					}
				}
			}
			lm=conv.end();
			if(it!=lm){
				a=b=it, b++;
				if(b!=lm){
					while(dir(im,*a,*b)!=1){
						dl[cn++]=*a;
						a=b, b++;
						if(a==lm)break;
					}
				}
			}
			if(it==conv.begin() || it==conv.end())conv.insert(im);
			else{
				a=it, a--;
				if(dir(*a, im, *it)==1)conv.insert(im);
			}
			for(k=0; k<cn; k++)conv.erase(dl[k]);
			j--;
		}
		if(conv.empty())dap[i]=0;
		else{
			a=it=conv.begin(), a++;
			cn=0;
			while(a!=conv.end()){
				if(xs[i]*(*it).a+(*it).b > xs[i]*(*a).a+(*a).b)dl[cn++]=*it;
				it=a, a++;
			}
			for(k=0; k<cn; k++)conv.erase(dl[k]);
			it=conv.begin();
			dap[i]=atan(1/(xs[i]*(*it).a+(*it).b));
		}
	}
	for(i=0; i<m; i++)printf("%.7lf\n", dap[i]);
	return 0;
}

Subtask #1

0.0 / 1.0

#	Verdict	Execution time	Memory	Grader output
1	Execution timed out	1000 ms	7524 KB	Program timed out
2	Halted	0 ms	0 KB	-