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? Solve this instance: [[-20, 5, 43], [-21, 19, -9, 50, 7], [-31, 4]]
Student:
[-20, 50, 4]