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QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#586978#784. 旋转卡壳houbur0 1ms5972kbC++201.5kb2024-09-24 16:53:402024-09-24 16:53:41

Judging History

你现在查看的是最新测评结果

  • [2024-10-16 12:18:36]
  • hack成功,自动添加数据
  • (/hack/1005)
  • [2024-09-24 16:55:39]
  • hack成功,自动添加数据
  • (/hack/888)
  • [2024-09-24 16:53:41]
  • 评测
  • 测评结果:0
  • 用时:1ms
  • 内存:5972kb
  • [2024-09-24 16:53:40]
  • 提交

answer

#include<iostream>
#include<cmath>
#include<algorithm>
using namespace std;
#define double long double
const int N=5e5+5;
int n,m,top,xx,yy;
struct sb{
	double x,y,k;
}e[N],st[N];
inline bool cmp(sb a,sb b){return (a.y==b.y)?(a.x<b.x):(a.y<b.y);}
inline double cross(sb a,sb b,sb c){return (b.x-a.x)*(c.y-a.y)-(c.x-a.x)*(b.y-a.y);}
inline double ddd(sb a,sb b){return (a.x-b.x)*(a.x-b.x)+(a.y-b.y)*(a.y-b.y);}
inline double dis(sb a,sb b,sb c){
	double k=(b.y-c.y)/(b.x-c.x);
	double bb=b.y-k*b.x;
	return fabs(k*a.x-a.y+bb)/sqrt(k*k+1);
}
inline bool cmpp(sb a,sb b){
	if(a.k!=b.k)return a.k<b.k;
	if(a.x==b.x)return a.y<b.y;
	return a.x<b.x;
}
signed main(){
	#ifndef ONLINE_JUDGE
	freopen("in.in","r",stdin);
	freopen("out.out","w",stdout);
	#endif
	ios::sync_with_stdio(0);
	cin.tie(0);cout.tie(0);
	cin>>n;
	for(int i=1;i<=n;i++)cin>>e[i].x>>e[i].y;
	sort(e+1,e+1+n,cmp);
	st[++top]=e[1];
	xx=st[top].x,yy=st[top].y;
	for(int i=2;i<=n;i++)e[i].k=atan2(e[i].y-yy,e[i].x-xx);
	sort(e+2,e+1+n,cmpp);
	st[++top]=e[2];
	for(int i=3;i<=n;i++){
		while(top>1&&cross(st[top-1],st[top],e[i])<0)top--;
		st[++top]=e[i];
	}
	int l=1,r=1;
	double ans=0;
	for(l=1;l<top;l++){
		int op=r;
		while(dis(st[r%top+1],st[l+1],st[l])>=dis(st[r],st[l+1],st[l])){
			r=r%top+1;
			if(r==op){
				ans=max({ans,ddd(st[r],st[l]),ddd(st[r],st[l+1]),ddd(st[l],st[l+1])});
				break;
			}
		}
		ans=max({ans,ddd(st[r],st[l]),ddd(st[r],st[l+1]),ddd(st[l],st[l+1])});
	}
	printf("%.7Lf",ans*ans);
	return 0;
}

Details

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Subtask #1:

score: 0
Wrong Answer

Test #1:

score: 0
Wrong Answer
time: 1ms
memory: 5972kb

input:

1000
0 0
-997615 -8573
-1988394 -28911
-2726572 -44296
-3491635 -60392
-4419752 -82814
-5298550 -105946
-5723430 -118453
-6608257 -147267
-7034966 -161982
-7563964 -181682
-8507871 -222865
-9499799 -271846
-10090186 -303547
-10400262 -322989
-10614073 -339725
-11081438 -378596
-11791568 -439127
-127...

output:

5664370055953136725586519728848896.0000000

result:

wrong answer 1st numbers differ - expected: '274339223.1895614', found: '5664370055953136360231999958417408.0000000', error = '20647321189063811313696768.0000000'

Subtask #2:

score: 0
Skipped

Dependency #1:

0%

Subtask #3:

score: 0
Skipped

Dependency #1:

0%