program p1;
var m,n,i,j,max:longint;
    a:array[1..16,1..16] of longint;
    t:array[1..16] of longint;
    f1,f2:text;

procedure citire;
 begin
  readln(f1,n,m);
  for i:=1 to n do
   for j:=1 to m do
    read(f1,a[i,j]);
 end;

procedure back(k:integer);
var sum,sum1:longint;
 begin
  if k=n+1 then
             begin
              sum:=0;
              for j:=1 to m do
               begin
                sum1:=0;
                for i:=1 to n do
                 sum1:=sum1+a[i,j]*t[i];
                sum:=sum+abs(sum1);
               end;
              if sum>max then max:=sum;
             end
            else
             begin
              t[k]:=1; back(k+1);
              t[k]:=-1; back(k+1);
             end;

 end;

begin
 assign(f1,'flip.in'); reset(f1);
 assign(f2,'flip.out'); rewrite(f2);

 citire;
 back(1);
 writeln(f2,max);

 close(f1); close(f2);
end.