求大神帮助 C语言程序急求

这个很容易

#include"reg51.h"
#define uchar unsigned char
#define uint unsigned int
#define led P0
sbit key=P1^0;
uchar t,a;
uchar code tab[]={0xff,0xfe,0xfc,0xfa,0xf0};
void delay(uint i)
{
while(i--);
}
void main()
{
TMOD=1;
TH0=(65536-50000)/256;
TL0=(65536-50000)%256;
EA=1;
ET0=1;
TR0=1;
while(1)
{
if(key==0)
{
delay(5000);
if(key==0)
{
if(a==4)a=0;
else a++;
}
}
}
}
void t0(void) interrupt 1
{
TH0=(65536-50000)/256;
TL0=(65536-50000)%256;
t++;
if(t==10)
{
t=0;
if(led!=0xff)led=0xff;
else led=tab[a];
}
}