单片机编程AT89C51 初始时数码管显示0000，按一次KEY1,数码管显示内容加1，按一次K

#include
#define uint unsigned int
#define uchar unsigned char
sbit wela=P2^7;
sbit dula=P2^6;
sbit key1=P3^4;//独立键盘，看你自己需要按哪个键
sbit key2=P3^5;//独立键盘
sbit key3=P3^6;//独立键盘
uint qian,bai,shi,ge,num;
uchar code table[]=
{0x3f,0x06,0x5b,0x4f,
0x66,0x6d,0x7d,0x07,
0x7f,0x6f};
void init()
{
num=0;
P3=0xff;
}
void delay(uchar z)
{
uchar x,y;
for(x=z;x>0;x--)
for(y=110;y>0;y--);
}
void display(uint n)
{
qian=n/1000;
bai=n%1000/100;
shi=n%1000%100/10;
ge=n%10;

wela=1;
P0=0xfe;
wela=0;
dula=1;
P0=table[qian];
dula=0;
delay(5);
P0=0xff;

wela=1;
P0=0xfd;
wela=0;
dula=1;
P0=table[bai];
dula=0;
delay(5);
P0=0xff;

wela=1;
P0=0xfb;
wela=0;
dula=1;
P0=table[shi];
dula=0;
delay(5);
P0=0xff;

wela=1;
P0=0xf7;
wela=0;
dula=1;
P0=table[ge];
dula=0;
delay(5);
P0=0xff;
}
void main()
{
init();
while(1)
{
display(num);
if(key1==0)
{
num++;
if(num==10000)//加到9999后为0
num=0;
while(!key1)
display(num);
}
if(key2==0)
{
num--;
if(num==-1)//减到0后为9999
num=9999;
while(!key2)
display(num);
}
if(key3==0)
{
num=0;
while(!key3)
display(num);
}
}
}