C++ 左移 << 和 右移 >>


先看例子:

#include 

using namespace std;

int main() {
    int num = 32;
    
    int half = num >> 1;
    int quarter = num >> 2;
    int doublenum = num << 1;
    int quadruple = num << 2;
    
    cout << "half = " << half << endl;
    cout << "quarter = " << quarter << endl;
    cout << "doublenum = " << doublenum << endl;
    cout << "quadruple = " << quadruple << endl;
    
    return 0;
}
half = 16 quarter = 8 doublenum = 64 quadruple = 128  

按位右移

数字为32=25,二进制为10000,右移一位为01000(左侧补零),即$2^4=16$。右移二位为00100,即$2^3=8$。

按位左移

右移一位为100000(右侧补零),即$2^6=64$。右移二位为1000000,即$2^7=128$。

注意:

不能出现cout<< 2>>1 <cout<< (2>>1) <>和<<运算级是一样的,并且这里是输入输出运算符,编译器会无法识别。