var a,b:array[1..20,1..20]of longint;
    n,m,i,j,l,k,q,s,s1:longint;
    max:longint;
    f,g:text;
begin
assign(f,'flip.in');reset(f);
assign(g,'flip.out');rewrite(g);
read(f,n,m);
for i:=1 to n do
    for j:=1 to m do
        begin
        read(f,a[i,j]);
        b[i,j]:=a[i,j];
        end;
max:=-1000000000;
for i:=1 to n do
    begin
    for j:=1 to m do
        b[i,j]:=b[i,j]*(-1);
    for j:=1 to m do
        begin
        for k:=1 to n do
            b[k,j]:=b[k,j]*(-1);
        s:=0;
        for k:=1 to n do
            for l:=1 to m do
                s:=s+b[k,l];
        if s>max then max:=s;
        for k:=1 to n do
            b[k,j]:=b[k,j]*(-1);
        end;
    for j:=1 to m do
        b[i,j]:=b[i,j]*(-1);
    end;
writeln(g,max);
close(f);
close(g);
end.