var a:array[1..17,1..17] of longint;
    v:array[1..17] of longint;
    f,q:text;
    n,i,j,m:byte;
    s:int64;

procedure maxsum;
var aux,sum:int64;
    i,j:byte;
begin
        sum:=0;
        aux:=0;
        for i:=1 to n do
        begin
                aux:=0;
                for j:=1 to m do begin aux:=aux+(v[j]*a[i,j]); end;
                if aux<0 then aux:=aux*-1;
                sum:=sum+aux;
        end;
        if sum>s then s:=sum;
end;
procedure back(k:integer);
var i:integer;
begin
      if k<=m then
        begin
                for i:=1 to 2 do
                begin
                        if i=1 then v[k]:=1
                               else v[k]:=-1;
                        back(k+1);
                end;

        end
        else maxsum;


end;
begin

assign(f,'flip.in'); reset(f);
assign(q,'flip.out'); rewrite(q);
readln(f,n,m);
for i:=1 to n do
begin
        v[i]:=1;
        for j:=1 to m do begin read(f,a[i,j]); s:=s+a[i,j]; end;
end;
back(1);
writeln(q,s);
close(f);
close(q);
end.