c语言的移位操作

http://tieba.baidu.com/f?kz=321200798    

    左移时总是移位和补零。

    右移时无符号数是移位和补零，此时称为逻辑右移;

    而有符号数大多数情况下是移位和补最左边的位（也就是补最高有效位），移几位就补几位,此时称为算术右移。 

 

       #include<iostream>

using namespace std;

 

void main() {

//unsigned short temp = 0x8151;

short temp = 0x8151;

cout << temp << endl;

printf("%x\n", temp);

 

unsigned char buf[] = {0, 0};

 

buf[1] = temp & 0x00FF;

temp = temp >> 8;

buf[0] = temp & 0x00FF;

 

//cout << buf[0] << " " << buf[1] << endl;

printf("%x\n", buf[0]);

printf("%x\n", buf[1]);

 

printf("%x\n", temp);

 

//unsigned short temp = 0x8151;

short temp1 = 0x7151;

cout << temp1 << endl;

printf("%x\n", temp1);

 

unsigned char buf1[] = {0, 0};

 

buf1[1] = temp1 & 0x00FF;

temp1 = temp1 >> 8;

buf1[0] = temp & 0x00FF;

 

//cout << buf[0] << " " << buf[1] << endl;

printf("%x\n", buf1[0]);

printf("%x\n", buf1[1]);

 

printf("%x\n", temp1);

 

short temp2 = 0x8151;

unsigned char buf2[] = {0, 0};

*((short *)buf2) = temp2;

printf("%x\n", buf2[0]);

printf("%x\n", buf2[1]);

 

getchar();

 

getchar();

}