输入年龄，根据年龄条件判断符合与否
age = 20
if age >= 18:
print ('your age is:',age)
print ('adult')
your age is: 20
adult
根据python的缩进规则及if语句的中的判断条件，使用else,如下
age = 15
if age >= 18:
print ('your age is:',age)
print ('adult')
else:
print ('your age is:',age)
print ('teenager')
your age is: 15
teenager
使用elfi语句做判断
age = 3
if age >= 18:
print ('adult')
elif age >= 6:
print ('teenager')
else:
print ('kid')
kid
- input的使用
birth = input('birth:')
if birth < 2000:
print ('00前')
else:
print ('00后')
birth:1988
---------------------------------------------------------------------------
TypeError Traceback (most recent call last)
<ipython-input-14-e5b461b8929a> in <module>()
1 birth = input('birth:')
----> 2 if birth < 2000:
3 print ('00前')
4 else:
5 print ('00后')
TypeError: '<' not supported between instances of 'str' and 'int'
birth值为str,字符类型无法对比，只有转换成数字类型才可以对比
s = input('birth:')
birth = int(s)
if birth < 2000:
print ('00前')
else:
print ('00后')
birth:1999
00前
s = input('birth:')
birth = int(s)
if birth < 2000:
print ('00前')
else:
print ('00后')
birth:abc
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
<ipython-input-16-69188189e7f4> in <module>()
1 s = input('birth:')
----> 2 birth = int(s)
3 if birth < 2000:
4 print ('00前')
5 else:
ValueError: invalid literal for int() with base 10: 'abc'
