LG4166

#include<bits/stdc++.h>

using namespace std;

#define gc c=getchar()
#define r(x) read(x)
#define db double

template<typename T>
inline void read(T&x){
    x=0;T k=1;char gc;
    while(!isdigit(c)){if(c=='-')k=-1;gc;}
    while(isdigit(c)){x=x*10+c-'0';gc;}x*=k;
}

const int N=2005;

struct Point{
    db x,y;
    inline bool operator < (const Point &a){return x==a.x?y<a.y:x<a.x;}
};
#define Vec Point
inline Vec operator + (const Point &a,const Point &b){return Point{a.x+b.x,a.y+b.y};}
inline Vec operator - (const Point &a,const Point &b){return Point{a.x-b.x,a.y-b.y};}
inline db  operator * (const Point &a,const Point &b){return a.x*b.y-a.y*b.x;}
inline db sqr(const db &a){return a*a;}
inline db norm(const Vec &a){return sqr(a.x)+sqr(a.y);}
inline bool cmp(const Vec &a,const Vec &b){
    return (a*b>0)||(a*b==0&&norm(a)<norm(b));
}

int sta[N],top;
inline int convex(Point *A,int n){
    Point tmp=A[1];
    for(int i=2;i<=n;++i)if(A[i]<tmp)tmp=A[i];
    for(int i=1;i<=n;++i)A[i]=A[i]-tmp;
    sort(A+1,A+n+1,cmp);
    sta[top=1]=1;
    for(int i=2;i<=n;++i){
        while(top>1&&(A[sta[top]]-A[sta[top-1]])*(A[i]-A[sta[top-1]])<=0)top--;
        sta[++top]=i;
    }
    for(int i=1;i<=top;++i)A[i]=A[sta[i]]+tmp;
    return top;
}

inline db area(const Point &a,const Point &b,const Point &c){
    return fabs((b-a)*(c-a));
}

Point P[N];

int main(){
    //freopen(".in","r",stdin);
    //freopen(".out","w",stdout);
    int n;scanf("%d",&n);
    for(int i=1;i<=n;++i){
        scanf("%lf%lf",&P[i].x,&P[i].y);
    }
    n=convex(P,n);
    db ans=0;
    for(int i=1;i<=n;++i){
        int a=i%n+1;
        int b=(i+2)%n+1;
        for(int j=i+2;j<=n;++j){
            while(a%n+1!=j&&area(P[i],P[j],P[a])<area(P[i],P[j],P[a%n+1]))a=a%n+1;
            while(b%n+1!=i&&area(P[i],P[j],P[b])<area(P[i],P[j],P[b%n+1]))b=b%n+1;
            ans=max(ans,area(P[i],P[j],P[a])+area(P[i],P[j],P[b]));
        }
    }
    printf("%.3lf\n",ans/2);
}