using c++

4. Write a program that recursively counts down from n. a) Create a void recursive function named countdown that accepts an integer n, and progressively decrements and outputs the value of n b) Test your function with a few values for n. 5. Write a program that recursively outputs a given integer in reverse a) Create a void recursive function that accepts an integer n and outputs the number backwards. b) Test your function with a few values for Write backward (3): 3 Write backward (12) 21 Write backward (123): 321 Write backward (2017): 7102