#include <reg51.h>
unsigned int a,s;
char i;
main()             //B=S/A
{
	s=P1<<8;
	a=P2<<8;
  	for (i=0;i<8;i+=1)
  	{
	 s=((s-(a>>1))>=0)? (s<<1)-a+1: s<<1;
  	}
	P3=s>>8;
}