Problem10720--ABC133 - B - Good Distance

10720: ABC133 - B - Good Distance

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Time Limit : 1.000 sec  Memory Limit : 512 MiB

Description

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?

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.

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 $X_{ik} \neq X_{jk}$.

Sample 1 Input

3 2
1 2
5 5
-2 8

Sample 1 Output

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 2 Input

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

Sample 2 Output

2

Sample 3 Input

5 1
1
2
3
4
5

Sample 3 Output

10

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