char n[10]={0,1,3,7,15,31,63},i;
void main()
{
trisa.f0=1;trisa.f1=1;trisb=0;portb=0;
loop:
while(porta.f0==0 && i<6)
                        {
                        i++;
                        portb=n[i];delay_ms(500);
                        }
while(porta.f1==0 && i>0)
                        {
                        i--;
                        portb=n[i];delay_ms(500);
                        }
goto loop;
}

char n[10]={0,1,3,7,15,31,63},i;
void main()
{
trisb=0b11000000;
portb=0b11000000;
loop:
while(portb.f6==0 && i<6)
                        {
                        i++;
                        portb=n[i];delay_ms(500);
                        }
while(portb.f7==0 && i>0)
                        {
                        i--;
                        portb=n[i];delay_ms(500);
                        }
goto loop;
}