Problem:
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

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.*;



public class Main{
    
    public static void main(String[] args){
        Scanner sc=new Scanner(System.in);
        int N=sc.nextInt();
        int C=sc.nextInt();
        int[][]D=new int[C][C];
        int[][]c=new int[N][N];
        for(int i=0;i<C;i++){
            for(int j=0;j<C;j++){
                D[i][j]=sc.nextInt();
            }
        }
        int[][]kazu=new int[3][50];
        for(int i=0;i<N;i++){
            for(int j=0;j<N;j++){
                c[i][j]=sc.nextInt()-1;
                kazu[(i+j)%3][c[i][j]]++;

            }
        }
        
        int ans=1000000000;
        int sum[][]=new int[3][C];
        for(int i=0;i<3;i++){
            for(int j=0;j<C;j++){
                for(int k=0;k<C;k++){
                    sum[i][j]+=D[k][j]*kazu[i][k];
                }
            }
        }
        for(int i=0;i<C;i++){
            for(int j=0;j<C;j++){
                for(int k=0;k<C;k++){
                    if((i==j)||(j==k)||(i==k)){
                        continue;
                    }
                    ans=Math.min(ans,sum[0][i]+sum[1][j]+sum[2][k]);
                }
            }
        }
        System.out.println(ans);
        

        
        

            

        
        
        
        
            

        
        

    }
    }