type mat=array[0..20,0..20] of longint;
     vec=array[1..20] of integer;
     vev=array[1..2] of integer;
var a:mat;
    v:vec;
    vv:vev;
    n,m,i,j:integer;
    f,g:text;
    s,smax:longint;
function valid(k:integer):boolean;
begin
valid:=true;end;
procedure final(n,m,k:integer);
var i,j:integer;ss:longint;
begin
s:=0;
for i:=1 to n do begin
ss:=0;
for j:=1 to m do
ss:=ss+a[i,j]*v[j];
if ss<0 then s:=s+ss*(-1)
        else s:=s+ss;
end;
if smax<s then smax:=s;
end;
procedure back(k:integer);
var i:integer;
begin
for i:=1 to 2 do begin
v[k]:=vv[i];
if valid(k) then if k=m then final(n,m,k)
                        else back(k+1);
                        end;
end;
begin
assign(f,'flip.in');assign(g,'flip.out');reset(f);rewrite(g);
readln(f,n,m);
for i:=1 to n do begin
for j:=1 to m do
read(f,a[i,j]);
readln(f);
end;
vv[1]:=1;vv[2]:=-1;
smax:=0;
back(1);
write(g,smax);close(f);close(g);end.