10720: ABC133 - B - Good Distance
[Creator : ]
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?
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:
```
$N$ $D$
$X_{11}$ $X_{12}$ $...$ $X_{1D}$
$X_{21}$ $X_{22}$ $...$ $X_{2D}$
$\vdots$
$X_{N1}$ $X_{N2}$ $...$ $X_{ND}$
```
```
$N$ $D$
$X_{11}$ $X_{12}$ $...$ $X_{1D}$
$X_{21}$ $X_{22}$ $...$ $X_{2D}$
$\vdots$
$X_{N1}$ $X_{N2}$ $...$ $X_{ND}$
```
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 $X_{ik} \neq X_{jk}$.
- $2 \leq N \leq 10$
- $1 \leq D \leq 10$
- $-20 \leq X_{ij} \leq 20$
- 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