code about led_shake

//write by:cyt
//Project Name:Led on/off
//Time:2017-2-10
#include<reg51.h>
void delay(int c)
{
    int a=38;
    int b=130;
    for(;c>0;c--)
    {
        for(;a>0;a--)
            for(;b>0;b--)
                ;
    }
}
void main()
{

    delay(1);

    while(1)
    {
        unsigned char i=0;
        delay(50);
        P0 = 0x00;
        delay(50);
        P0 = 0xff;
    }
}