#include <stdio.h>
int main() {
double xa, ya, xb, yb, xc, yc, xd, yd;
scanf ("%lf%lf", &xa, &ya); // читаем координаты точки A
scanf ("%lf%lf", &xb, &yb); // читаем координаты точки D
scanf ("%lf%lf", &xc, &yc); // читаем координаты точки C
scanf ("%lf%lf", &xd, &yd); // читаем координаты точки D
printf (
(((xd - xa)*(yb-ya)-(yd-ya)*(xb-xa))*((xc - xa)*(yb-ya)-(yc-ya)*(xb-xa)) >= 0) &&
(((xd - xb)*(yc-yb)-(yd-yb)*(xc-xb))*((xa - xb)*(yc-yb)-(ya-yb)*(xc-xb)) >= 0) &&
(((xd - xc)*(ya-yc)-(yd-yc)*(xa-xc))*((xb - xc)*(ya-yc)-(yb-yc)*(xa-xc)) >= 0 )?
"yes": "no");
return 0;
}
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MAkwCTIJMAkwCTIJNQk1CjAJMAkyCTAJMAkyCTEJMQotMQktMQkxCS0xCTAJMQkwCTAKLTEJLTEJMQktMQkwCTEJMQkzCi0xCS0xCTEJLTEJMAkxCTAuNQkwCi0xCS0xCTEJLTEJMAkxCTAJMQotMgktMgkxCS0xCTAJMQkwCTAKLTEJLTEJMQktMQkwCTEJMgky
0 0 2 0 0 2 5 5
0 0 2 0 0 2 1 1
-1 -1 1 -1 0 1 0 0
-1 -1 1 -1 0 1 1 3
-1 -1 1 -1 0 1 0.5 0
-1 -1 1 -1 0 1 0 1
-2 -2 1 -1 0 1 0 0
-1 -1 1 -1 0 1 2 2