拆包、交换变量的值

<1> 对返回的数据直接拆包
def get_my_info():
high = 178
weight = 100
age = 18
return high, weight, age

#result = get_my_info()
#print(result)

my_high, my_weight, my_age = get_my_info()
print(my_high)
print(my_weight)
print(my_age)
总结：
拆包时要注意，需要拆的数据的个数要与变量的个数相同，否则程序会异常
除了对元组拆包之外，还可以对列表、字典等拆包

  In [17]: a, b = (11, 22)
  In [18]: a
  Out[18]: 11
  In [19]: b
  Out[19]: 22

  In [20]: a, b = [11, 22]
  In [21]: a
  Out[21]: 11
  In [22]: b
  Out[22]: 22

  In [23]: a, b = {"m":11, "n":22}  # 取出来的是key，而不是键值对
  In [24]: a
  Out[24]: 'm'
  In [25]: b
  Out[25]: 'n'

<2> 交换2个变量的值
#第1种方式
#a = 4
#b = 5
#c = 0

#c = a
#a = b
#b = c

#print(a)
#print(b)

#第2种方式
#a = 4
#b = 5
#a = a+b # a=9, b=5
#b = a-b # a=9, b=4
#a = a-b # a=5, b=4
#print(a)
#print(b)

#第3种方式
a, b = 4, 5
a, b = b, a

print(a)
print(b)