python中使用enumerate函数遍历元素实例

比如我们有一个["one","two","there"]的列表，我们需要在列表的每个元素前面加上他的编号

代码如下:

i = 0
seq = ["one","two","three"]
for element in seq:
seq[i] = '%d: %s' % (i, seq[i])
i += 1
print seq

['0: one', '1: two', '2: three']

使用enumerate函数，我们可以简化我们的代码，省去定义计数用的临时变量

代码如下:

seq = ["one","two","three"]
for i, element in enumerate(seq):
seq[i] = '%d: %s' % (i, seq[i])
print seq

['0: one', '1: two', '2: three']

代码如下:

seq = ["one","two","three"]
print ['%d: %s'% (i,element) for i,element in enumerate(seq) ]

['0: one', '1: two', '2: three']