python中flat将嵌套列表中的元素按顺序排列在一个列表中

Posted 2023-04-22

flat([[1,2,3],[4,5,6],[7,8,9]]) = [1,2,3,4,5,6,7,8,9]
def flat(nestedlist):
outcome = []
请问怎么做
return outcome

按照你的要求编写的Python程序如下

def flat(nestedlist):

outcome = [nestedlist[i][j] for i in range(len(nestedlist)) for j in range(len(nestedlist[i]))]

return outcome

print(flat([[1,2,3],[4,5,6],[7,8,9]]))

源代码(注意源代码的缩进)

参考技术A 2018-01-12693

python(列表2)

1.remove(删除指定值的元素)

x = [‘to‘,‘be‘,‘or‘,‘not‘,‘to‘,‘be‘]

x.remove(‘be‘)

x

[‘to‘,‘or‘,‘not‘,‘to‘,‘be‘]

2.reverse(按照相反的顺序排列列表中的元素)

s = [1,2,3]

s.reverse()

s

[3,2,1]

 

3.sort(按顺序排列)

x = [2,3,4,5,7,9,6,0]

x.sort()

x

[0,2,3,4,5,6,7,9]

 

sorted函数

x = [4,6,2,1,7,9]

y = sorted(x)

x

[4,6,2,1,7,9]

y

[1,2,4,6,7,9]

4.高级排序：方法sort接受两个可选参数:key和reverse

x = [‘aardfgasgas‘,‘sasasasas‘,‘a‘,‘aaa‘]

x.sort(key = len)按照长度来排序

x

[‘a‘,‘aaa‘,‘sasasasas‘,‘aardfgasgas‘]

x = [4,6,5,7,2,1]

x.sort(reverse=True)指定一个值true or false,是否按照相反的顺序排序

x

[1,2,4,5,6,7]