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#include <stdio.h>
typedef struct {
short x;
short y;
} point_t;
point_t a, b, c, d;
long long cross_product(point_t m, point_t n, point_t p, point_t q)
{
return (n.x - m.x) * (q.y - p.y) - (q.x - p.x) * (n.y - m.y);
}
char convex()
{
if (cross_product(a, c, c, b) * cross_product(a, c, c, d) > 0)
return 0;
if (cross_product(b, d, d, a) * cross_product(b, d, d, c) > 0)
return 0;
return 1;
}
void swap(point_t *m, point_t *n)
{
short tmp = m->x;
m->x = n->x;
n->x = tmp;
tmp = m->y;
m->y = n->y;
n->y = tmp;
}
long long dot_product(point_t m, point_t n, point_t p, point_t q)
{
return (n.x - m.x) * (q.x - p.x) + (n.y - m.y) * (q.y - p.y);
}
char f2()
{
return !dot_product(a, b, b, c);
}
char f3()
{
return !dot_product(a, c, b, d);
}
char f4()
{
return (a.x + c.x == b.x + d.x) && (a.y + c.y == b.y + d.y);
}
int main()
{
scanf("%hd %hd %hd %hd %hd %hd %hd %hd",
&a.x, &a.y, &b.x, &b.y, &c.x, &c.y, &d.x, &d.y);
if (!convex()) {
swap(&a, &b);
if (!convex())
swap(&b, &c);
}
char val = 5;
if (f4()) {
val = 4;
if (f2())
val = 2;
if (f3())
val--;
}
printf("%hhd\n", val);
return 0;
}
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