经典示例:
while (x > 0) { x /= 2; }这会是:
Iteration | x----------+------- 0 | x 1 | x/2 2 | x/4 ... | ... ... | ... k | x/2^k
2 k = x→两端均施加对数→k = log(x)

经典示例:
while (x > 0) { x /= 2; }这会是:
Iteration | x----------+------- 0 | x 1 | x/2 2 | x/4 ... | ... ... | ... k | x/2^k
2 k = x→两端均施加对数→k = log(x)