100993: [AtCoder]ABC099 D - Good Grid

Memory Limit:256 MB Time Limit:2 S
Judge Style:Text Compare Creator:
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Description

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

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

Sample Output 1

3
  • 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

4 3
0 12 71
81 0 53
14 92 0
1 1 2 1
2 1 1 2
2 2 1 3
1 1 2 2

Sample Output 2

428

Input

题意翻译

给出一个 $N\times N$ 的矩阵,$c_{i,j}\in[1,C]$ 定义一个 **好的矩阵** 满足: - 若 $i+j\equiv x+y\ (\text{mod}\ 3)$,有 $c_{i,j}=c_{x,y}$ - 若 $i+j\not\equiv x+y\ (\text{mod}\ 3)$,有 $c_{i,j}\ne c_{x,y}$ 你可以随意更改矩阵使其变成 **好的矩阵** (更改后仍有 $c'_{i,j}\in[1,C]$) 若将一个数字 $X$ 改为 $Y$,会造成 $D_{X,Y}$ 的 **错误值** 请你求出使得 **错误值之和最小** 的修改方案,输出其错误值

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