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