#include <stdio.h>
#include <stdlib.h>

int main()
{
    unsigned char a,b;
    a = 0x55;
    b = a ^ 0xff;
    printf("%x",b);
    b = a & 0x7f;
    printf("%x",b);
    b = a & 0x01;
    printf("%x",b);
    b = a | 1;
    printf("%x",b);
    b = a | 0xaa;

}