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Contest: Task: Related: TaskC TaskE

Score : $400$ points

Problem Statement

There is a grid with $N$ rows and $N$ columns of squares. Let $(i,j)$ be the square at the $i$-th row from the top and the $j$-th column from the left.

These squares have to be painted in one of the $C$ colors from Color $1$ to Color $C$. Initially, $(i,j)$ is painted in Color $c_{i,j}$.

We say the grid is a good grid when the following condition is met for all $i,j,x,y$ satisfying $1 \leq i,j,x,y \leq N$:

If $(i+j) \% 3=(x+y) \% 3$, the color of $(i,j)$ and the color of $(x,y)$ are the same.
If $(i+j) \% 3 \neq (x+y) \% 3$, the color of $(i,j)$ and the color of $(x,y)$ are different.

Here, $X \% Y$ represents $X$ modulo $Y$.

We will repaint zero or more squares so that the grid will be a good grid.

For a square, the wrongness when the color of the square is $X$ before repainting and $Y$ after repainting, is $D_{X,Y}$.

Find the minimum possible sum of the wrongness of all the squares.

Constraints

$1 \leq N \leq 500$
$3 \leq C \leq 30$
$1 \leq D_{i,j} \leq 1000 (i \neq j),D_{i,j}=0 (i=j)$
$1 \leq c_{i,j} \leq C$
All values in input are integers.

Input

Input is given from Standard Input in the following format:

$N$ $C$
$D_{1,1}$ $...$ $D_{1,C}$
$:$
$D_{C,1}$ $...$ $D_{C,C}$
$c_{1,1}$ $...$ $c_{1,N}$
$:$
$c_{N,1}$ $...$ $c_{N,N}$

Output

If the minimum possible sum of the wrongness of all the squares is $x$, print $x$.

Sample Input 1

Sample Output 1

Repaint $(1,1)$ to Color $2$. The wrongness of $(1,1)$ becomes $D_{1,2}=1$.
Repaint $(1,2)$ to Color $3$. The wrongness of $(1,2)$ becomes $D_{2,3}=1$.
Repaint $(2,2)$ to Color $1$. The wrongness of $(2,2)$ becomes $D_{3,1}=1$.

In this case, the sum of the wrongness of all the squares is $3$.

Note that $D_{i,j} \neq D_{j,i}$ is possible.

Sample Input 2