In c++: (Average of digits in an integer) Write a function that computes the average of the digits in an integer. Use the following function header: double averageDigits(long n) For example, averageDigits(936) returns 6.0 ((9 + 3 + 6)/3). (Hint: Use the % operator to extract digits, and the / operator to remove the extracted digit. For instance, to extract 6 from 936, use 936 % 10 (= 6). To remove 6 from 936, use 936 / 10 (= 93). Use a loop to repeatedly extract and remove the digit until all the digits are extracted. Write a test program that prompts the user to enter an integer and displays the sum of all its digits.