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,', name
hello,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 v
12345 |
while
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>>> a=0
>>> while a<10:
a=a+1
print a
12345678910 |
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 |