let g(x,y)(s,t)=(x-.s,y-.t)and h(x,y)(s,t)=x*.t-.y*.s;;let rec f()=f(Scanf.scanf"%f %f %f %f %f %f %f %f
"(fun a b c d e i j k->let l=h(g(a,b)(e,i))(g(j,k)(a,b))and m=h(g(c,d)(a,b))(g(j,k)(c,d))and n=h(g(e,i)(c,d))(g(j,k)(e,i))in print_endline(if l>0.&&m>0.&&n>0.||l<0.&&m<0.&&n<0.then"YES"else"NO")));;try f()with _->()