Problem:
Parallel/Orthogonal

For given two lines s1 and s2, print "2" if they are parallel, "1" if they are orthogonal, or "0" otherwise.

s1 crosses points p0 and p1, and
s2 crosses points p2 and p3.

Input

The entire input looks like:

q (the number of queries)
1st query
2nd query
...
qth query

Each query consists of integer coordinates of the points p0, p1, p2, p3 in the following format:

xp0 yp0 xp1 yp1 xp2 yp2 xp3 yp3

Output

For each query, print "2", "1" or "0".

Constraints

1 ≤ q ≤ 1000

-10000 ≤ xpi, ypi ≤ 10000

p0 ≠ p1 and
p2 ≠ p3.

Sample Input 1

3
0 0 3 0 0 2 3 2
0 0 3 0 1 1 1 4
0 0 3 0 1 1 2 2

Sample Output 1

2
1
0

Solution in C# (judge verdict: Accepted)

using System;
//using System.Collections.Generic;
//using System.Linq;
//using Vector = CGL.Point;
//using Line = CGL.Segment;
//using Polygon = System.Collections.Generic.List<CGL.Point>;


namespace CGL
{
    class Program
    {
        static void Main(string[] args)
        {
            var q = scan[0];
            for (int i = 0; i < q; i++)
            {
                var t = scan;
                var p = new Point[4];
                for (int j = 0; j < 4; j++)
                {
                    p[j] = new Point(t[j * 2], t[j * 2 + 1]);
                }

                if ((p[1] - p[0]).Cross(p[3] - p[2]) == 0) Console.WriteLine(2);
                else if ((p[1] - p[0]).Dot(p[3] - p[2]) == 0) Console.WriteLine(1);
                else Console.WriteLine(0);
            }
        }

        static int[] scan { get { return Array.ConvertAll(Console.ReadLine().Split(), int.Parse); } }
    }
    
    struct Point
    {
        static readonly double EPS = 1E-10;
        double x, y;
        public Point(double x, double y)
        {
            this.x = x;
            this.y = y;
        }

        public static Point operator +(Point a, Point b) { return new Point(a.x + b.x, a.y + b.y); }
        public static Point operator -(Point a, Point b) { return new Point(a.x - b.x, a.y - b.y); }
        public static Point operator *(double k, Point a) { return new Point(k * a.x, k * a.y); }
        public static Point operator /(double k, Point a) { return new Point(a.x / k, a.y / k); }
        
        public double Abs { get { return Math.Sqrt(Norm); } }  
        public double Norm { get { return x * x + y * y; } }

        public static bool operator <(Point a, Point b) { return Math.Abs(a.x - b.x) > EPS ? a.x < b.x : a.y < b.y; }
        public static bool operator >(Point a, Point b) { return Math.Abs(a.x - b.x) > EPS ? a.x > b.x : a.y > b.y; }
        public static bool operator ==(Point a, Point b) { return Math.Abs(a.x - b.x) < EPS && Math.Abs(a.y - b.y) < EPS; }
        public static bool operator !=(Point a, Point b) { return Math.Abs(a.x - b.x) >= EPS || Math.Abs(a.y - b.y) >= EPS; }

        public override bool Equals(object p){  return Math.Abs(x - ((Point)p).x) < EPS && Math.Abs(y - ((Point)p).y) < EPS; }
        public override int GetHashCode(){ return x.GetHashCode() ^ y.GetHashCode(); }

        public double Dot(Point p) { return x * p.x + y * p.y; }
        public double Cross(Point p) { return x * p.y - y * p.x; }

    }
    /*struct Segment
    {
        Point p1, p2;
        public Segment(Point p1, Point p2)
        {
            this.p1 = p1;
            this.p2 = p2;
        }
    }
    struct Circle
    {
        Point c; double r;
        public Circle(Point c, double r)
        {
            this.c = c;
            this.r = r;
        }

    }*/
}