var a:array[1..16,1..16]of longint;
    n,i,j,m,s:longint;
    f,g:text;
procedure linie(i:integer);
var l:integer;
    s1,s2:longint;
begin
s2:=0;s1:=0;
for l:=1 to m do
    begin
    s1:=s1+a[i,l];
    end;
for l:=1 to m do
    begin
    s2:=s2+(0-a[i,l]);
    end;
if s2>s1 then
   begin
   for l:=1 to m do
       begin
       a[i,l]:=0-a[i,l];
       end; end;
end;
procedure coloana(j:integer);
var l:integer;
    s1,s2:longint;
begin
s2:=0;s1:=0;
for l:=1 to n do
    begin
    s1:=s1+a[l,j];
    end;
for l:=1 to n do
    begin
    s2:=s2+(0-a[l,j]);
    end;
if s2>s1 then
   begin
   for l:=1 to n do
       begin
       a[l,j]:=0-a[l,j];
       end; end;
end;
begin
assign(f,'flip.in');reset(f);
assign(g,'flip.out');rewrite(g);
readln(f,n,m);
for i:=1 to n do
    begin
    for j:=1 to m do
        begin
        read(f,a[i,j]);
        end;
    readln(f);
    end;
s:=0;
for i:=1 to n do
    begin
    linie(i);
    end;
for j:=1 to m do
    begin
    coloana(j);
    end;
for i:=1 to n do
    for j:=1 to m do
        begin
        s:=s+a[i,j];
        end;
write(g,s);
close(f);close(g);
end.