import java.io.*;
import java.util.*;


public class Prob2{
	
	static int[][]array;
	static int n;
	static int s;
	static int size;
	static int size2;
	
	static String filename = "DATA21.txt";
	static FileInputStream fis;
	static DataInputStream dis;
	
	public static void readIn(){
		
		
		
		try{
			
		
		
		n = Integer.parseInt(dis.readLine());	
		s = Integer.parseInt(dis.readLine());	
		
		size = (int)(Math.sqrt(n));
		size2 = (int)(Math.sqrt(s));
		
		array = new int [size][size];
		
		for(int i=0; i<size; i++){
			StringTokenizer bla = new StringTokenizer(dis.readLine());
			for(int j=0; j<size; j++){
				array[i][j] = Integer.parseInt(bla.nextToken());
			}
		}
		
		
		
			
		}catch (IOException e){}
		
		
	}//end read line
	
	public static int addSquare(int row, int col){
		int sum = 0;
		for (int i = 0; i < size2; i++){
			for (int j = 0; j < size2; j++){
				sum += array[row+i][col+j];
			}
		}
		return sum;
	}
	
	
	public static void main(String[] arg) throws IOException{
		
		
		int [] ans = new int[5];
		
		
		fis = new FileInputStream("DATA21.txt");
		dis = new DataInputStream(fis);
		
		
		for (int z = 0; z <5; z++){
		
		readIn();
		
		int high = 0;
		
		for (int i = 0; i <= size-size2; i++){
			for (int j = 0; j <= size-size2; j++){
				if (addSquare(i,j) > high)
				high = addSquare(i,j);
			}	
		}
		
		
		
			ans[z] = high;
		
		
		
		
		
		
			
		}	
	
		
		
		String file = "OUT21.txt";
		FileOutputStream fos;
		PrintWriter p;
		
			fos = new FileOutputStream(file);
			p = new PrintWriter(fos);
			for (int i = 0; i < 5; i++){
				p.println(ans[i]);
			}			
			p.close();
	
	}
	
}