program gametk;
const
  fi='gametk.in';  fo='gametk.out';
type
  arr1=array[1..500,1..500] of longint;
  arr2=array[0..1,0..500,-1..3000] of longint;
  arr3=array[0..10000] of longint;
var
  fin,fout:text;
  n,m,r,t,ans,l:longint;
  graph:arr1;  f:arr2;  item:arr3;

  function max(i,j:longint):longint;
  begin
    if i>j then max:=i
    else max:=j;
  end;

  procedure swap(var i,j:longint);
  var
    tmp:longint;
  begin
    tmp:=i;  i:=j;  j:=tmp;
  end;

  procedure init;
  var
    i,j:longint;
  begin
    assign(fin,fi);  reset(fin);
    readln(fin,n,m,r,t);
    for i:=1 to m do begin
      for j:=1 to n do
        read(fin,graph[i,j]);
      readln(fin);
    end;
    close(fin);
  end;

  procedure qsort(i,j:longint);
  var
    l,r,mid:longint;
  begin
    l:=i;  r:=j;  mid:=item[(i+j) shr 1];
    repeat
      while item[l]>mid do l:=l+1;
      while item[r]<mid do r:=r-1;
      if l<=r then begin
        swap(item[l],item[r]);
        l:=l+1;  r:=r-1;
      end;
    until l>r;
    if r>i then qsort(i,r);
    if j>l then qsort(l,j);
  end;

  procedure main;
  var
    i,j,k,d,p,q,x,y:longint;
  begin
    p:=0;  q:=0;
    for i:=1 to m do begin
      p:=1-p;
      for j:=1 to n do begin
        for k:=0 to q do item[k]:=0;
        q:=0;
        for x:=1 to r do
          for y:=1 to r do
            if graph[i+x-1,j+y-1]<>0 then begin
              q:=q+1;
              item[q]:=graph[i+x-1,j+y-1];
            end;
        qsort(1,q);
        for k:=2 to q do
          item[k]:=item[k-1]+item[k];
        l:=l+q;
        if (i=1) and (j=1) then begin
          for k:=0 to q do
            f[i,j,k]:=item[k];
          continue;
        end;
        for k:=i+j-2 to i+j+l-2 do begin
          f[p,j,k]:=0;
          if k>t then break;
          for d:=i+j-3 to k-1 do
              f[p,j,k]:=max(f[p,j,k],max(f[p,j-1,d],f[1-p,j,d])+item[k-d-1]);
          if   f[p,j,k]>ans then ans:=f[p,j,k];
        end;
      end;
    end;
  end;

  procedure print;
  begin
    assign(fout,fo);  rewrite(fout);
    writeln(fout,ans);  close(fout);
  end;

begin
  init;
  main;
  print;
end.