var n,m:byte;     a:array [1..17,1..17] of longint;   
b:array [1..17] of boolean;   
max:longint;   
  procedure citeste;   
    var f:text;   
        i,j:byte;   
   begin   
     assign(f,'flip.in');   
     reset(f);   
     readln(f,n,m);   
     for i:=1 to n do for j:=1 to m do read(f,a[i,j]);   
    close(f);   
   end;   
 procedure urmatorul;   
   var i:byte;   
   begin   
     i:=1;   
     while b[i] do begin   
                    b[i]:=false;   
                       i:=i+1;   
                      end;   
        b[i]:=true;   
      end;   
    procedure verif;   
  var i,j:byte;   
     s,t:longint;   
   begin   
     t:=0;   
     for i:=1 to n do begin   
                       s:=0;   
                        for j:=1 to m do if b[j] then s:=s+a[i,j]   
                                                else s:=s-a[i,j];   
                        if s<0 then t:=t-s   
                               else t:=t+s;   
                    end;   
    if t>max then max:=t;   
 end;   
 procedure calc;   
   var x,i:longint;   
   begin   
     x:=1;   
     for i:=1 to 17 do b[i]:=false;   
     for i:=1 to m do x:=x*2;   
     for i:=1 to x do begin   
                        verif;   
                        urmatorul;   
                    end;   
   end;   
 procedure afiseaza;   
   var f:text;   
   begin   
     assign(f,'flip.out');   
     rewrite(f);   
     write(f,max);   
     close(f);   
  end;   
 begin   
   citeste;   
  calc;   
    afiseaza;   
end.