var f1,f2:text;
    i,j,g,n,m,h,s,max,k:longint;
    a:array[0..17,0..17] of longint;
    b,v:array[0..20] of longint;

procedure back;
begin
        for g:=0 to 1 shl m-1 do
        begin
                s:=0;
                k:=g;
                j:=0;
                while k>0 do
                begin
                        inc(j);
                        v[j]:=k mod 2;
                        k:=k div 2;
                end;
                for i:=1 to m do
                begin
                        if v[i]=1 then
                                h:=-1
                        else h:=1;
                        for j:=1 to n do
                                b[j]:=b[j]+a[j,i]*h;
                end;
                for i:=1 to n do
                begin
                        s:=s+abs(b[i]);
                        b[i]:=0;
                end;
                if s>max then
                        max:=s;
        end;
end;

begin
        assign(f1,'flip.in');
        reset(f1);
        assign(f2,'flip.out');
        rewrite(f2);
        read(f1,n,m);
        for i:=1 to n do
                for j:=1 to m do
                        read(f1,a[i,j]);
        back;
        writeln(f2,max);
        close(f1);
        close(f2);
end.