Geometry

// NgJaBach: Forever Meadow <3

#include<bits/stdc++.h>

using namespace std;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
typedef long long int ll;
typedef unsigned long long ull;
#define pb push_back
#define pob pop_back
#define mp make_pair
#define upb upper_bound
#define lwb lower_bound
#define bend(a) a.begin(),a.end()
#define rev(x) reverse(bend(x))
#define mset(a) memset(a, 0, sizeof(a))
#define fi first
#define se second
#define gcd __gcd
#define getl(s) getline(cin, s);
#define setpre(x) fixed << setprecision(x)
#define endl '\n'
const int N=1050,M=1000000007;
const ll INF=1e18+7;
struct point{
    int x,y;
    void input(){
        cin>>x>>y;
        return;
    }
}gay[N];
bool sexy(point A,point B){
    if(A.x==B.x) return A.y<B.y;
    return A.x<B.x;
}
int cross_product(point u,point v){
    return u.x*v.y-u.y*v.x;
}
int determine_convexhull(point A,point B,point C){ // A <-- B --> C
    point BA,BC;
    BA.x=A.x-B.x;
    BA.y=A.y-B.y;
    BC.x=C.x-B.x;
    BC.y=C.y-B.y;
    return cross_product(BA,BC);
}
double dist(point A,point B){
    double x,y;
    x=A.x-B.x; y=A.y-B.y;
    return sqrt(x*x+y*y);
}
double polygon_area(vector<point>vec){
    vec.pb(vec[0]);
    double sum=0,two=2;
    for(int i=1;i<vec.size();++i){
        sum+=(double)cross_product(vec[i-1],vec[i]);
    }
    sum/=two;
    return abs(sum);
}
double polygon_perimeter(vector<point>vec){
    vec.pb(vec[0]);
    double sum=0;
    for(int i=1;i<vec.size();++i){
        sum+=dist(vec[i-1],vec[i]);
    }
    return sum;
}
int main(){
    ios_base::sync_with_stdio(NULL); cin.tie(nullptr); cout.tie(nullptr);
//    freopen("BAOLOI.inp","r",stdin);
//    freopen("BAOLOI.out","w",stdout);
    int n,m;
    cin>>n;
    for(int i=1;i<=n;++i) gay[i].input();
    sort(gay+1,gay+n+1,sexy);
    vector<point>up,down,res;
    point Lp,Rp;
    up.pb(gay[1]); down.pb(gay[1]);
    Lp=gay[1]; Rp=gay[n];
    for(int i=2;i<=n;++i){
        if(i==n or (determine_convexhull(Lp,gay[i],Rp)<0)){
            while(up.size()>=2 and !(determine_convexhull(up[up.size()-2],up[up.size()-1],gay[i])<0)) up.pob();
            up.pb(gay[i]);
        }
        if(i==n or (determine_convexhull(Lp,gay[i],Rp)>0)){
            while(down.size()>=2 and !(determine_convexhull(down[down.size()-2],down[down.size()-1],gay[i])>0)) down.pob();
            down.pb(gay[i]);
        }
    }
    m=up.size();
    for(int i=0;i<m;++i) res.pb(up[i]);
    m=down.size();
    for(int i=m-2;i>0;--i) res.pb(down[i]);
//  for(auto tmp:res) cout<<tmp.x<<" "<<tmp.y<<endl;
    cout<<res.size()<<endl;
    cout<<setpre(3)<<polygon_perimeter(res)<<endl<<polygon_area(res);
    return 0;
}
/*
==================================+
INPUT:                            |
------------------------------    |
8
7 1
16 2
1 5
13 8
11 9
5 10
2 8
7 5
------------------------------    |
==================================+
OUTPUT:                           |
------------------------------    |

------------------------------    |
==================================+
*/