Instructions: 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.
Input: [[42, -11], [-37, -14, -25, -21], [24, 40, 31, -46]]
Output:
[42, -14, -44160]