1 #include<iostream>
 2 #include<cstdio>
 3 #include<cstring>
 4 #include<cmath>
 5 #include<queue>
 6 #include<algorithm>
 7 using namespace std;
 8 int n,k;
 9 const int maxn = 105;
10 int maze[maxn][maxn],dp[maxn][maxn];
11 int dfs(int p,int q){
12     if(dp[p][q]) return dp[p][q];
13     int l,r,d,u;
14     int ans = 0,maxx = 0;
15     l = p - k;
16     r = p + k;
17     if(l<0) l = 0;
18     if(r>=n) r = n-1;
19     for(int i = l; i<=r; i++){
20         if(maze[i][q]>maze[p][q]){
21             ans = dfs(i,q);
22             if(ans>maxx) maxx = ans;
23         }
24     }
25     u = q + k;
26     d = q - k;
27     if(d<0) d = 0;
28     if(u>=n) u = n-1;
29     for(int i = d; i<=u; i++){
30         if(maze[p][i]>maze[p][q]){
31             ans = dfs(p,i);
32             if(ans>maxx) maxx = ans;
33         }
34     }
35     dp[p][q] = maxx + maze[p][q];
36     return dp[p][q];
37 }
38 void input(){
39         while(scanf("%d%d",&n,&k)!=EOF&&n != -1&&k != -1){
40             for(int i = 0; i<n; i++)
41                 for(int j = 0; j<n; j++)
42                 scanf("%d",&maze[i][j]);
43             memset(dp,0,sizeof(dp));
44             printf("%d\n",dfs(0,0));
45         }
46 }
47 int main()
48 {
49     input();
50     return 0;
51 }