#include <iostream>
#include <cstring>
#include <cstdio>
#include <algorithm>
using namespace std;

const int maxn = 5e4+10;

typedef struct Point{
    int x,y;
    bool operator <(const struct Point &B)const{
        if(x==B.x)  return y<B.y;
        return x<B.x;
    }
    bool operator ==(const struct Point &B)const{
        return (x-B.x)==0&&(y-B.y)==0;
    }
}Vector;

Vector p[maxn],st[maxn];

int Cross(Point a,Point b,Point o)        {
    return (a.x - o.x) * (b.y - o.y) - (b.x - o.x) * (a.y - o.y);
}

int ConvexHull(Point *p,int n,Point *st){
    sort(p,p+n);
    n = unique(p,p+n)-p;
    int m=0;
    for(int i=0;i<n;i++){
        while(m>1&&Cross(st[m-1],p[i],st[m-2])<=0) m--;
        st[m++]=p[i];
    }
    int k=m;
    for(int i=n-2;i>=0;i--){1
        while(m>k&&Cross(st[m-1],p[i],st[m-2])<=0) m--;
        st[m++]=p[i];
    }
    if(n>1) m--;
    return m;
}

int dis(Point a,Point b){
    return (a.x-b.x)*(a.x-b.x)+(a.y-b.y)*(a.y-b.y);
}
//旋转卡壳求凸包的宽度
double rotating_calipers(Point *p,int n){
    int k = 1;
    double ans = 0x7FFFFFFF;
    p[n] = p[0];
    for(int i=0;i<n;i++){
        while(fabs(cross(p[i],p[i+1],p[k])) < fabs(cross(p[i],p[i+1],p[k+1])))
             k = (k+1) % n;
        double tmp = fabs(cross(p[i],p[i+1],p[k]));
        double d   = dist(p[i],p[i+1]);
        ans = min(ans,tmp/d);
    }
    return ans;
}
int main()
{
    int n;
    while(~scanf("%d",&n)){
        for(int i=0;i<n;i++){
            scanf("%d%d",&p[i].x,&p[i].y);
        }
        int m = ConvexHull(p,n,st);
        int ans = rotatint_calipers(st,m);
        printf("%d\n",ans);
    }
    return 0;
}

#include <iostream>
#include <cstring>
#include <cstdio>
#include <algorithm>
#include <cmath>
using namespace std;

const int maxn = 5e4+10;

const double eps = 1e-10;

int dcmp(double x){
    if(fabs(x)<=0) return 0;
    if(x>0) return 1;
    else return -1;
}

typedef struct Point{
    double x,y;
    bool operator <(const struct Point &B)const{
        if(x==B.x)  return y<B.y;
        return x<B.x;
    }
    bool operator ==(const struct Point &B)const{
        return dcmp(x-B.x)==0&&dcmp(y-B.y)==0;
    }
}Vector;

Vector p[maxn],st[maxn];

double Cross(Point a,Point b,Point o)        {
    return (a.x - o.x) * (b.y - o.y) - (b.x - o.x) * (a.y - o.y);
}

int ConvexHull(Point *p,int n,Point *st){
    sort(p,p+n);
    n = unique(p,p+n)-p;
    int m=0;
    for(int i=0;i<n;i++){
        while(m>1&&Cross(st[m-1],p[i],st[m-2])<=0) m--;
        st[m++]=p[i];
    }
    int k=m;
    for(int i=n-2;i>=0;i--){
        while(m>k&&Cross(st[m-1],p[i],st[m-2])<=0) m--;
        st[m++]=p[i];
    }
    if(n>1) m--;
    return m;
}

double dis(Point a,Point b){
    return sqrt((a.x-b.x)*(a.x-b.x)+(a.y-b.y)*(a.y-b.y));
}

double rotating_calipers(Point *p,int n){
    double ans = 0;
    int j,k;
    for(int i=0;i<n;i++){
        j=(i+1)%n;
        k=(j+1)%n;
        while(fabs(Cross(p[i+1],p[k],p[i]))<fabs(Cross(p[i+1],p[k+1],p[i])))
            k=(k+1)%n;
        while(j!=i&&k!=i){
            ans=max(ans,fabs(Cross(p[i],p[k],p[j])));
            while(fabs(Cross(p[i],p[k],p[j]))<fabs(Cross(p[i],p[(k+1)%n],p[j])))
                k=(k+1)%n;
            j=(j+1)%n;
        }
    }
    return ans/2.0;
}

int main()
{
    int n;
    while(~scanf("%d",&n)){
        if(n==-1) break;
        for(int i=0;i<n;i++)
            scanf("%lf%lf",&p[i].x,&p[i].y);
        int m = ConvexHull(p,n,st);
        //cout<<"m "<<m<<endl;
        if(m<3) puts("0.00");
        if(m==3) printf("%.2lf\n",fabs(Cross(st[0],st[1],st[2]))/2.0);
        else{
            double ans = rotating_calipers(st,m);
            printf("%.2lf\n",ans);
        }
    }
    return 0;
}

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