#include<iostream>
#include<queue>
#include<cstdio>
#include<cstring>
using namespace std;
const int inf=0x3f3f3f3f;
struct edge
{
    int to,nxt,c,f;
}e[30011];
int n,k,cur,ans,cnt=1;
int dist[30011],used[30011],pree[30011],prev[30011],g[30011];
void link(int u,int v,int f,int c)
{
    e[++cnt].nxt=g[u];
    g[u]=cnt;
    e[cnt].f=f;
    e[cnt].to=v;
    e[cnt].c=c;
}
void ins(int u,int v,int f,int c)
{
    link(u,v,f,c);
    link(v,u,0,-c);
}
int Min(int x,int y)
{
    return x<y?x:y;
}
bool spfa()
{
    queue<int>q;
    memset(dist,-1,sizeof(dist));
    memset(used,0,sizeof(used));
    dist[0]=0;
    q.push(0);
    while(!q.empty())
    {
        int u=q.front(); q.pop(); 
        used[u]=0;
        for(int i=g[u];i;i=e[i].nxt)
        {
            int v=e[i].to,w=e[i].c;
            if(e[i].f&&dist[v]<dist[u]+w)
            {
                dist[v]=dist[u]+w;
                prev[v]=u; pree[v]=i;
                if(!used[v])
                {
                    q.push(v); 
                    used[v]=1;
                }
            }
        }
    }
    return dist[10010]!=-1;
}
int MinCostFlow()
{
    int u=10010,sum=inf;
    while(u)
    {
        e[pree[u]].f--;
        e[pree[u]^1].f++;
        u=prev[u];
    }
//    cout<<dist[10010]<<endl;
    return dist[10010];
}
void MinFlow()
{
    while(spfa())
    {
        cur+=MinCostFlow();
        if(cur>ans) ans=cur;
    }
    printf("%d",ans);
}
int main()
{
    scanf("%d%d",&n,&k);
    for(int i=1;i<=n;i++)
    {
        for(int j=1;j<=n;j++)
        {
            int x; scanf("%d",&x);
            ins((i-1)*n+j,(i-1)*n+j+n*n,1,x);
            ins((i-1)*n+j,(i-1)*n+j+n*n,k,0);
            if(i!=n)
            {
                ins((i-1)*n+j+n*n,i*n+j,k,0);
            }
            if(j!=n)
            {
                ins((i-1)*n+j+n*n,(i-1)*n+j+1,k,0);
            }
        }
    }
    ins(0,1,k,0);
    ins(n*n*2,10010,k,0);
    MinFlow();
    return 0;
}