10.27.5

#include<stdio.h>

#include<math.h>

int main()

{

/* int a,b,c,d;

scanf("%d,%d\n%d,%d",&a,&b,&c,&d);

printf("%.1f",sqrt(pow(a-c,2)+pow(b-d,2)));*/

  double a,b,c,d,e,f,g,h,i;

scanf("%lf%lf%lf%lf%lf%lf%lf%lf%lf",&a,&b,&c,&d,&e,&f,&g,&h,&i);

if((int)((a*c+b*c)*2-d*e-f*g)%(int)(h*i)==0)

printf("%d",(int)((a*c+b*c)*2-d*e-f*g)/(int)(h*i));

else

printf("%d",((int)((a*c+b*c)*2-d*e-f*g)/(int)(h*i)+1));  

return 0;

}