#include<bits/stdc++.h>

using namespace std;

const int MAXN=+;

const int MAXM=;

const int INF=0x3f3f3f3f;

struct Edge{

    int to,next,cap,flow,cost;

}edge[MAXM];

int head[MAXN],tol;

int pre[MAXN],dis[MAXN];

bool vis[MAXN];

int n;

void init(){

    tol=;

    memset(head,-,sizeof(head));

}

void addedge(int u,int v,int cap,int cost){

    edge[tol].to=v;

    edge[tol].cap=cap;

    edge[tol].cost=cost;

    edge[tol].flow=;

    edge[tol].next=head[u];

    head[u]=tol++;

    edge[tol].to=u;

    edge[tol].cap=;

    edge[tol].cost=-cost;

    edge[tol].flow=;

    edge[tol].next=head[v];

    head[v]=tol++;

}

bool spfa(int s,int t){

    queue<int> q;

    memset(dis,INF,sizeof(dis));

    memset(vis,false,sizeof(vis));

    memset(pre,-,sizeof(pre));

    dis[s]=;

    vis[s]=true;

    q.push(s);

    while(!q.empty()){

        int u=q.front();

        q.pop();

        vis[u]=false;

        for(int i=head[u];i!=-;i=edge[i].next){

            int v=edge[i].to;

            if(edge[i].cap>edge[i].flow&&dis[v]>dis[u]+edge[i].cost){

                dis[v]=dis[u]+edge[i].cost;

                pre[v]=i;

                if(!vis[v]){

                    vis[v]=true;

                    q.push(v);

                }

            }

        }

    }

    if(pre[t]==-)

        return false;

    else

        return true;

}

int minCostMaxFlow(int s,int t,int &cost){

    int flow=;

    cost=;

    while(spfa(s,t)){

        int Min=INF;

        for(int i=pre[t];i!=-;i=pre[edge[i^].to]){

            if(Min>edge[i].cap-edge[i].flow)

                Min=edge[i].cap-edge[i].flow;

        }

        for(int i=pre[t];i!=-;i=pre[edge[i^].to]){

            edge[i].flow+=Min;

            edge[i^].flow-=Min;

            cost+=edge[i].cost*Min;

        }

        flow+=Min;

    }

    return flow;

}

void show(int s){

    bool vis[];

    queue<int> q;

    vis[s]=;

    q.push(s);

    while(!q.empty()){

        int u=q.front();

        q.pop();

        cout<<"u="<<u<<endl;

        for(int i=head[u];i!=-;i=edge[i].next){

            int v=edge[i].to;

            if(vis[v]==){

                vis[v]=;

                q.push(v);

            }

        }

    }

    cout<<endl;

}

/* EK end */

int a[][];

int k;

inline int getid(int i,int j,int isout){

    return (i-)*n+j+isout*(n*n);

}

int main(){

    init();

    scanf("%d%d",&n,&k);

    int si=*n*n+,so=*n*n+;

    addedge(si,so,k,);//最多走k次

    int t=*n*n+;

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

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

            int c;

            scanf("%d",&c);

            addedge(getid(i,j,),getid(i,j,),,-c);

            //拿走它，获得价值，费用是相反数

            addedge(getid(i,j,),getid(i,j,),INF,);

            //不拿就不拿呗

        }

    }

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

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

            if(i+<=n)

                addedge(getid(i,j,),getid(i+,j,),INF,);

            if(j+<=n)

                addedge(getid(i,j,),getid(i,j+,),INF,);

        }

    }

    addedge(so,getid(,,),INF,);

    addedge(getid(n,n,),t,INF,);

    //show(si);

    int cost=;

    int flow=minCostMaxFlow(si,t,cost);

    printf("%d\n",-cost);

}