var f,g:text;
    a,b:array[0..1001] of longint;
    c:array[-37..37] of longint;
    numar,i,md,j,n:longint;
begin
assign(f,'trapez.in');reset(f);
assign(g,'trapez.out');rewrite(g);
read(f,n);
for i:=1 to n do read(f,a[i],b[i]);
for i:=1 to n do
 for j:=1 to n do
  if i<>j then
   if b[i]<>b[j] then begin
    md:=(a[j]-a[i])div(b[j]-b[i]);
    inc(c[md]);
   end;
for i:=-37 to 37 do
 if c[i]<>0 then inc(numar);
writeln(g,numar);
close(f);
close(g);
end.