位移问题，有一段不明白！
#include <stdio.h>#include <stdlib.h>
void main()
{
unsigned long input_IP;
unsigned int BeginByte,MidByte,ThirdByte,EndByte;
unsigned int_rotate=0x07;
printf("******************************************************\n");
printf("** This program is to show how to parse a IP address**\n");
printf("******************************************************\n");
printf("Please enter the IP address(hex) you want parse:");
scanf("%lx",&input_IP);
BeginByte = (input_IP >> 24) & ~(~0 << 8);
MidByte = (input_IP >> 16) & ~(~0 << 8);
ThirdByte = (input_IP >> 8 ) & ~(~0 << 8);
EndByte = input_IP & ~(~0 << 8);
printf("******************************************************\n");
printf("The IP address after parsed is: %d.%d.%d.%d\n",BeginByte,MidByte,ThirdByte,EndByte);
/*介绍两个循环移位函数*/
printf("******************************************************\n");
printf("%u after rotated twice is =%u\n",int_rotate,_rotl(int_rotate,2));
printf("%u after rotated once is =%u\n",int_rotate,_rotr(int_rotate,1));
scanf("%d",int_rotate);
}
BeginByte = (input_IP >> 24) & ~(~0 << 8);
MidByte = (input_IP >> 16) & ~(~0 << 8);
ThirdByte = (input_IP >> 8 ) & ~(~0 << 8);
EndByte = input_IP & ~(~0 << 8);
这一段不明白
