# -*- coding: utf-8 -*-

L = [

    ['Apple', 'Google', 'Microsoft'],

    ['Java', 'Python', 'Ruby', 'PHP'],

    ['Adam', 'Bart', 'Lisa']

]

print(len(L))

print(L[0][0])

print(L[1][1])

print(L[2][2])

print(L[2][-1])

结果：

f:/work/L1_3.py

3

Apple

Python

Lisa

Lisa