python之控制流
https://www.cnblogs.com/evablogs/p/6691776.html
条件判断
简单if语句
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>>>name='lily'>>>if name='lily': print 'hello,', namehello,lily |
if-else
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>>>score=90>>>if score>=80: print 'very good'else: print 'keep trying'very good |
if-elif-else
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>>> age=18>>> if age>=18: print 'adult'elif age<18: print 'teenager'else: print 'please enter the correct age'adult |
循环
for
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>>> L=[1,2,3,4,5]>>> for v in L: print v12345 |
while
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>>> a=0>>> while a<10: a=a+1 print a12345678910 |
退出循环
break与continue区别：
break：退出循环体
利用 while True 无限循环配合 break 语句，计算 1 + 2 + 4 + 8 + 16 + ... 的前20项的和。
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>>> s = 0>>> x = 1>>> n = 1>>> while True: if n>20: break s=s+x x=x*2 n=n+1 print s 13715316312725551110232047409581911638332767655351310712621435242871048575 |
continue：退出本次循环，不执行此次循环的循环体，继续下一个循环
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>>> b=[0,1,2,6,3,4,1,5]>>> for v in b: if v<2: continue print v 26345 |
