#include <cstdio>

 #include <cstring>

 #include <algorithm>

 #define N1 67010

 #define M1 400010

 #define L1 45

 using namespace std;

 const int inf=0x3f3f3f3f;

 int gint()

 {

     int ret=,fh=;char c=getchar();

     while(c<''||c>''){if(c=='-')fh=-;c=getchar();}

     while(c>=''&&c<=''){ret=ret*+c-'';c=getchar();}

     return ret*fh;

 }

 struct Edge{

 int to[M1<<],nxt[M1<<],flow[M1<<],head[N1],cte;

 void ae(int u,int v,int f)

 {

     cte++; to[cte]=v; nxt[cte]=head[u];

     head[u]=cte; flow[cte]=f;

 }

 }e;

 int dep[N1],que[M1],cur[N1],n,m,h,D,hd,tl,S,T;

 int bfs()

 {

     int x,j,v;

     memset(dep,-,sizeof(dep)); memcpy(cur,e.head,sizeof(cur));

     hd=,tl=; que[++tl]=S; dep[S]=;

     while(hd<=tl)

     {

         x=que[hd++];

         for(j=e.head[x];j;j=e.nxt[j])

         {

             v=e.to[j];

             if( dep[v]==- && e.flow[j]> )

             {

                 dep[v]=dep[x]+;

                 que[++tl]=v;

             }

         }

     }

     return dep[T]!=-;

 }

 int dfs(int x,int limit)

 {

     int j,v,flow,ans=;

     if(!limit||x==T) return limit;

     for(j=cur[x];j;j=e.nxt[j])

     {

         v=e.to[j]; cur[x]=j;

         if( dep[v]==dep[x]+ && (flow=dfs(v,min(limit,e.flow[j]))) )

         {

             e.flow[j]-=flow; limit-=flow;

             e.flow[j^]+=flow; ans+=flow;

             if(!limit) break;

         }

     }

     return ans;

 }

 int Dinic()

 {

     int mxflow=,j,v,ans=;

     while(bfs())

         mxflow+=dfs(S,inf);

     return mxflow;

 }

 int xx[]={-,,,},yy[]={,,,-};

 int v[L1][L1][L1],id[L1][L1][L1];

 inline int check(int x,int y){return (x<||y<||x>n||y>m)?:;}

 int main()

 {

     scanf("%d%d%d%d",&n,&m,&h,&D);

     int i,j,k,x,y,w,p; e.cte=; S=; T=n*m*(h+)+;

     for(k=;k<=h+;k++) for(i=;i<=n;i++) for(j=;j<=m;j++) id[k][i][j]=(k-)*n*m+(i-)*m+j;

     for(k=;k<=h;k++) for(i=;i<=n;i++) for(j=;j<=m;j++)

     {

         w=v[k][i][j]=gint(), x=id[k][i][j];

         e.ae(x,x+n*m,w), e.ae(x+n*m,x,);

         if(k<=D) continue;

         //x+=n*m;

         for(p=;p<;p++)

         {

             if(!check(i+xx[p],j+yy[p])) continue;

             y=id[k-D][i+xx[p]][j+yy[p]];

             e.ae(x,y,inf); e.ae(y,x,);

         }

     }

     for(i=;i<=n;i++) for(j=;j<=m;j++) e.ae(S,id[][i][j],inf), e.ae(id[][i][j],S,);

     for(i=;i<=n;i++) for(j=;j<=m;j++) e.ae(id[h+][i][j],T,inf), e.ae(T,id[h+][i][j],);

     printf("%d\n",Dinic());

     return ;

 }