Problems

# Axis of symmetry of the quadrilateral

# Axis of symmetry of the quadrilateral

Given the coordinates of the successive vertices of a convex quadrilateral. How many axes of symmetry does this figure?

**Input**

In one line contains **8** digits**x _{1}**,

**y**,

_{1}**x**,

_{2}**y**,

_{2}**x**,

_{3}**y**,

_{3}**x**,

_{4}**y**– coordinates of the vertices of a quadrilateral.

_{4}**-50** ≤** x _{1}**,

**y**,

_{1}**x**,

_{2}**y**,

_{2}**x**,

_{3}**y**,

_{3}**x**,

_{4}**y**≤

_{4 }**50**

**Output**

One number - the number of axes of symmetry.

Input example #1

0 0 0 5 5 5 5 0

Output example #1

4