如何用一句语句判断一个数是否是power of 2？（2的指数幂）
从网上看到的，想了很久，没招。
哪个牛人给说说？
a***x 发帖数: 26368
2
Determining if an integer is a power of 2
unsigned int v; // we want to see if v is a power of 2
bool f; // the result goes here
f = (v & (v - 1)) == 0;
Note that 0 is incorrectly considered a power of 2 here. To remedy this, use:
f = !(v & (v - 1)) && v;
