enumerate()函数用于将一个可遍历的数据对象(如列表、元组或字符串)组合为一个索引序列,同时列出数据和数据下标,一般用在for循环当中
语法
enumerate(sequence, [start=0])
参数
sequence:一个序列、迭代器或其他支持迭代对象
start:下标起始位置
返回值
返回enumerate(枚举)对象
seasons = ['Spring', 'Summer', 'Fall', 'Winter']
# [(0, 'Spring'), (1, 'Summer'), (2, 'Fall'), (3, 'Winter')]
print(list(enumerate(seasons)))
# [(1, 'Spring'), (2, 'Summer'), (3, 'Fall'), (4, 'Winter')]
print(list(enumerate(seasons, start=1))) # 下标从1开始
普通的for循环
i = 0
seq = ['one', 'two', 'three']
for element in seq:
print(i, seq[i])
i = i + 1
# 0 one
# 1 two
# 2 three
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