第一题代码：

文件：

shiyan6-1.c

wget http://121.43.169.106:5244/p/Halo/shiyan6-4.c?sign=mWee4N15Blqhu6yQHspY9NwShRFyX1aVi8DuaJqaiaw=:0

源码：

#include<stdio.h>

int main(){
    unsigned int a = 0x12345678;
    printf("1:%.8x\n", a&0xff000000);
    printf("2:%.8x\n", a&0x000000ff);
    printf("3:%.8x\n", (~a) & 0xffffff00);
    printf("4:%.8x\n",a|0x000000ff);
    return 0;
}