var a: array [0..1001,0..1001] of integer;
    s: array [1..1000,1..2] of integer;
    max,i,j,ki,km,i1,j1,m: integer;
BEGIN
   readln(max);
   for i:=1 to max do
    for j:=1 to max do
     readln(a[i,j]);

	m :=0;
   for i:=1 to max do
    for j:=1 to max do
     if a[i,j] = 1 then
     begin
	  m := m+1;
	  ki := 1;
      km := 0;
      s[1,1] := i;
      s[1,2] := j;

	  while (km < ki) do
	  begin
     	  km := km+1;
	   a[s[km,1],s[km,2]] := 0;

       if (a[s[km,1]+1,s[km,2]] = 1)
       then
        begin
	   	 ki := ki+1;
         s[ki,1] := s[km,1]+1;
         s[ki,2] := s[km,2];
        end;

	   if (a[s[km,1]-1,s[km,2]] = 1)
       then
        begin
		 ki := ki+1;
		 s[ki,1] := s[km,1]-1;
         s[ki,2] := s[km,2];
        end;

	   if (a[s[km,1],s[km,2]+1] = 1)
       then
        begin

		 ki := ki+1;
		 s[ki,1] := s[km,1];
         s[ki,2] := s[km,2]+1;
        end;

	   if (a[s[km,1],s[km,2]-1] = 1)
       then
        begin
         s[ki,1] := s[km,1];
         s[ki,2] := s[km,2]-1;
		 ki := ki+1;
        end;

	   if (a[s[km,1]+1,s[km,2]-1] = 1)
       then
        begin
	     ki := ki+1;
         s[ki,1] := s[km,1]+1;
         s[ki,2] := s[km,2]-1;
        end;

 	   if (a[s[km,1]-1,s[km,2]+1] = 1)
       then
        begin
		 ki := ki+1;
		 s[ki,1] := s[km,1]-1;
         s[ki,2] := s[km,2]+1;
        end;

	   if (a[s[km,1]-1,s[km,2]-1] = 1)
       then
        begin
		 ki := ki+1;
		 s[ki,1] := s[km,1]-1;
         s[ki,2] := s[km,2]-1;
        end;

	   if (a[s[km,1]+1,s[km,2]+1] = 1)
       then
        begin
		 ki := ki+1;
		 s[ki,1] := s[km,1]+1;
         s[ki,2] := s[km,2]+1;
        end;
	  end;

      writeln();
	  writeln(m);

	 end;
END.