Pagini recente » Cod sursa (job #2487957) | Cod sursa (job #1794865) | Cod sursa (job #1071356) | Cod sursa (job #2946591) | Cod sursa (job #1877946)
#include <fstream>
#include <cmath>
#include <algorithm>
#include <iomanip>
#define nmax 100005
using namespace std;
ifstream f("rubarba.in");
ofstream g("rubarba.out");
int n,k;
long double sol=1LL*(1<<30)*(1<<30);
struct point{int x;int y;} p[nmax],s[nmax];
struct pointdouble{long double x;long double y;};
long long determinant(const point &a,const point &b,const point &c)
{
return (1LL*b.x-a.x)*(c.y-a.y)-(1LL*c.x-a.x)*(b.y-a.y);
}
int sortcomp(const point &a,const point &b)
{
return determinant(p[1],a,b)>0;
}
long double distanta(const point &a,const point &b)
{
return sqrt(double((1ll*a.x-b.x)*(a.x-b.x)+(1ll*a.y-b.y)*(a.y-b.y)));
}
long double distantadouble(const pointdouble &a,const pointdouble &b)
{
return sqrt(((a.x-b.x)*(a.x-b.x)+(a.y-b.y)*(a.y-b.y)));
}
void solve(point a,point b)
{
if (!(a.x<=b.x))
swap(a,b);
long double m,b1,b2,dist=0;
m=(1.0*b.y-a.y)/(b.x-a.x);
b1=1.0*(1.0*a.y*(b.x-a.x)-1.0*a.x*(b.y-a.y))/(b.x-a.x);
pointdouble p,l,c,aux;
l.x=a.x;l.y=a.y;
c.x=b.x;c.y=b.y;
for (int i=1;i<=k;i++)
if ((s[i].x!=a.x||s[i].y!=a.y)&&(s[i].x!=b.x||s[i].y!=b.y)) {
if (b.x==a.x) {
p.x=a.x;
p.y=s[i].y;
}else
if (b.y==a.y) {
p.x=s[i].x;
p.y=a.y;
}else {
b2=s[i].y+1.0*s[i].x/m;
p.x=m*(1.0*b2-b1)/(m*m+1);
p.y=m*p.x+b1;
}
aux.x=s[i].x;
aux.y=s[i].y;
dist=max(dist,distantadouble(aux,p));
if (b.x!=a.x) {
if (p.x>c.x)
c=p;
if (p.x<l.x)
l=p;
}
else {
c.y=max(c.y,p.y);
l.y=min(l.y,p.y);
}
}
sol=min(sol,dist*distantadouble(l,c));
}
int main()
{
int i,j=1;
f>>n;
for (i=1;i<=n;i++) {
f>>p[i].x>>p[i].y;
if (p[i].y<p[j].y||(p[i].y==p[j].y&&p[i].x<p[j].x))
j=i;
}
swap(p[1],p[j]);
sort(p+2,p+n+1,sortcomp);
s[++k]=p[1];
s[++k]=p[2];
for (i=3;i<=n;i++) {
while (k>=2&&determinant(s[k-1],s[k],p[i])<0)
k--;
s[++k]=p[i];
}
s[k+1]=p[1];
for (i=1;i<=k;i++)
solve(s[i],s[i+1]);
g<<setprecision(2)<<fixed<<sol<<'\n';
return 0;
}