Problem:
Score : 200 points

Problem Statement

There are N points in a D-dimensional space.

The coordinates of the i-th point are (X_{i1}, X_{i2}, ..., X_{iD}).

The distance between two points with coordinates (y_1, y_2, ..., y_D) and (z_1, z_2, ..., z_D) is \sqrt{(y_1 - z_1)^2 + (y_2 - z_2)^2 + ... + (y_D - z_D)^2}.

How many pairs (i, j) (i < j) are there such that the distance between the i-th point and the j-th point is an integer?

Constraints

All values in input are integers.

2 \leq N \leq 10

1 \leq D \leq 10

-20 \leq X_{ij} \leq 20

No two given points have the same coordinates. That is, if i \neq j, there exists k such that X_{ik} \neq X_{jk}.

Input

Input is given from Standard Input in the following format:

N D
X_{11} X_{12} ... X_{1D}
X_{21} X_{22} ... X_{2D}
\vdots
X_{N1} X_{N2} ... X_{ND}

Output

Print the number of pairs (i, j) (i < j) such that the distance between the i-th point and the j-th point is an integer.

Sample Input 1

3 2
1 2
5 5
-2 8

Sample Output 1

1

The number of pairs with an integer distance is one, as follows:

The distance between the first point and the second point is \sqrt{|1-5|^2 + |2-5|^2} = 5, which is an integer.

The distance between the second point and the third point is \sqrt{|5-(-2)|^2 + |5-8|^2} = \sqrt{58}, which is not an integer.

The distance between the third point and the first point is \sqrt{|-2-1|^2+|8-2|^2} = 3\sqrt{5}, which is not an integer.

Sample Input 2

3 4
-3 7 8 2
-12 1 10 2
-2 8 9 3

Sample Output 2

2

Sample Input 3

5 1
1
2
3
4
5

Sample Output 3

10

Solution in C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;

namespace AtCoder
{
    public static class Program
    {
        static void Main()
        {
            var array = Console.ReadLine().Split(' ').Select(i => i.ToInt()).ToArray();
            var N = array[0];
            var D = array[1];
            var points = new int[N][];
            for (int i = 0; i < N; i++)
            {
                points[i] = Console.ReadLine().Split(' ').Select(x => x.ToInt()).ToArray();
            }

            int count = 0;
            for (int y = 0; y < points.Length - 1; y++)
            {
                for (int y2 = y + 1; y2 < points.Length; y2++)
                {
                    if (IsDistanceInteger(points[y], points[y2])) ++count;
                }
            }
            Console.WriteLine(count);
        }

        private static bool IsDistanceInteger(int[] y, int[] z)
        {
            var distance = Math.Sqrt(y.Zip(z, (a, b) => (int)Math.Pow(Math.Abs(a - b),2d)).Sum());
            return distance == Math.Floor(distance);
        }

        public static int ToInt(this string param) => int.Parse(param);
    }
}