#include<iostream>

#include<cstdio>

#include<algorithm>

#include<cmath>

#include<cstring>

#include<string>

#include<stack>

#include<queue>

#include<deque>

#include<set>

#include<vector>

#include<map>

#include<functional>

#define fst first

#define sc second

#define pb push_back

#define mem(a,b) memset(a,b,sizeof(a))

#define lson l,mid,root<<1

#define rson mid+1,r,root<<1|1

#define lc root<<1

#define rc root<<1|1

#define lowbit(x) ((x)&(-x)) 

using namespace std;

typedef double db;

typedef long double ldb;

typedef long long ll;

typedef unsigned long long ull;

typedef pair<int,int> PI;

typedef pair<ll,ll> PLL;

const db eps = 1e-;

const int mod = 1e9+;

const int maxn = 5e6+;

const int maxm = 2e6+;

const int inf = 0x3f3f3f3f;

const db pi = acos(-1.0);

struct point{

    double x, y;

    point(double x = , double y = ):x(x), y(y){}

};

double length(point a, point b){

    return sqrt((a.x-b.x)*(a.x-b.x)+(a.y-b.y)*(a.y-b.y));

}

bool ok(double a){

    return a >  &&fabs(a-(int)(a+eps)) < eps;

}

int main(){

    point a, b, c;

    while(scanf("%lf %lf", &a.x, &a.y) != ){

        scanf("%lf %lf %lf %lf", &b.x, &b.y, &c.x, &c.y);

        double ab = length(a, b);

        double ac = length(a, c);

        double bc = length(b, c);

        double A = acos((ab*ab+ac*ac-bc*bc)/(2.0*ab*ac));

        double B = acos((ab*ab+bc*bc-ac*ac)/(2.0*ab*bc));

        double C = acos((ac*ac+bc*bc-ab*ab)/(2.0*ac*bc));

        int flg = ;

        for(int i = ; i <= ; i++){

            if(ok(A*i/pi) && ok(B*i/pi) && ok(C*i/pi)){

                flg = i;

                break;

            }

        }

        printf("%d\n", flg);

    }

    return ;

}