[项目实践] 在项目实战中提升代码效率的的一次应用实践-----使用列表解析式输出当前android设备的CPU核数

1、先按照初学者思维代码应该是这样的

 #coding:utf-8
 import os
 text = os.popen("adb shell command cat /proc/cpuinfo",'r').read().split("\n")
 i = 0
 for j in text:
     if "processor\t:" in j:
         i += 1
 if i == 1:
     print ("单核")
 elif i == 2:
     print ("2核")
 elif i == 3:
     print ("3核")
 elif i == 4:
     print ("4核")
 elif i == 5:
     print ("5核")
 elif i == 6:
     print ("6核")
 elif i == 7:
     print ("7核")
 elif i == 8:
     print ("8核")

上面的代码也没啥毛病，也能得出正确的结果，但代码有20多行，实在是影响代码的执行效率了

2、接下来看这个

 #coding:utf-8
 import os
 i = 0
 cores = ["单核","2核","3核","4核","5核","6核","7核","8核"]
 text = os.popen("adb shell command cat /proc/cpuinfo",'r').read().split("\n")
 lst = [i+1 for j in text if "Processor\t:" in j]
 cpu_cores = cores[len(lst)-1]
 print (cpu_cores)

得出的结果跟上面的一样，那这样看看哪个的执行效率更好些