Teacher: In this task you will be given a list, of lists, of integers. For every inner list contained in the input list, you should multiply every even number in that list. The output should be a list of integers with the same length as the number of lists in the input list. If there are no even numbers in an inner list you should output 0 for that list.
Teacher: Now, understand the problem? If you are still confused, see the following example:
[[7, -3, -3, 11], [-6, -6, -5, 2], [-8, 4, -3]]
Solution: [0, 72, -32]
Reason: The first inner list has no even integers, so the first number in the output is 0. The second list has -6, -6, 2 for even integers so the second output is 72. The third list has -8, 4 as even numbers so the third output is -32. This is a good example.

Now, solve this instance: [[45, -48, -20, -50, -47], [32, 40], [-12, -49], [21, -45, 4, -7, 3]]
Student:
[-48000, 1280, -12, 4]