字典和列表的迭代

字典中经常需要对keys及values一起迭代

例:定义一个字典

user_info = {'zhangsan': 123, 'lisi': '123', 'wangwu': 456}

for key, value in user_info.items():
    print('%s:%s'%(key,value))

输出结果：

lisi:123
wangwu:456
zhangsan:123

 

例：对比下列表的迭代

for i in [(1,1),(2,2),(3,3)]:
    print(i)
for i ,k in [(1,1),(2,2),(3,3)]:
    print(i,k)

=(1, 1)
(2, 2)
(3, 3)
1 1
2 2
3 3

 

python enumerate()函数

for 循环使用 enumerate

>>>seq = ['one', 'two', 'three']
>>> for i, element in enumerate(seq): ... print i, element
...
0 one
1 two
2 three