#include <bits/stdc++.h>
using namespace std;
INT main() {
    double x1,y1,x2,y2,x3,y3,x4,y4,a,b,c,d,e,f;
    cin>>x1>>y1>>x2>>y2>>x3>>y3>>x4>>y4;
    a=sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
    b=sqrt((x2-x3)*(x2-x3)+(y2-y3)*(y2-y3));
    c=sqrt((x3-x4)*(x3-x4)+(y3-y4)*(y3-y4));
    d=sqrt((x1-x4)*(x1-x4)+(y1-y4)*(y1-y4));
    e=sqrt((x1-x3)*(x1-x3)+(y1-y3)*(y1-y3));
    f=sqrt((x2-x4)*(x2-x4)+(y2-y4)*(y2-y4));
    IF (a==b&&b==c&&c==d){
        IF (e==f){
            cout << 4;
        }
        ELSE{
            cout << 2;
        }
    }
    ELSE{
        IF (a==c&&b==d&&e==f){
            cout<< 2 <<endl;
        }
        ELSE IF(e == f){
            cout<<"1"<<endl;
        }
        ELSE{
            cout << 0;
        }
    }
    RETURN 0;
}