//dp[i][j]表示从点i,j处开始能获得的最多cheese

#include <iostream>

#include <string.h>

#include <stdio.h>

using namespace std;

int n,k,dp[101][101],map[101][101];

int dfs(int a,int b){

    if(dp[a][b]) return dp[a][b];

    dp[a][b] = map[a][b];

    for(int i = 1;i<=k;i++){

        if(a+i<n&&map[a+i][b]>map[a][b])

            dp[a][b] = max(dp[a][b],dfs(a+i,b)+map[a][b]);

        if(a-i>=0&&map[a-i][b]>map[a][b])

            dp[a][b] = max(dp[a][b],dfs(a-i,b)+map[a][b]);

        if(b-i>=0&&map[a][b-i]>map[a][b])

            dp[a][b] = max(dp[a][b],dfs(a,b-i)+map[a][b]);

        if(b+i<n&&map[a][b+i]>map[a][b])

            dp[a][b] = max(dp[a][b],dfs(a,b+i)+map[a][b]);

    }

    return dp[a][b];

}

int main(void){

    while(scanf("%d %d",&n,&k)!=EOF){

        if(n==-1&&k==-1) break;

        for(int i = 0;i<n;i++){

            for(int j = 0;j<n;j++)

                scanf("%d",&map[i][j]);

        }

        memset(dp,0,sizeof(dp));

        printf("%d\n",dfs(0,0));

    }

}