Please use C programming language

Write a program that reads in a positive integer and then displays that integer reversed. If the number entered is not a positive integer, then an error message should be displayed. Note: You need to read the integer in as an integer and not a string. Include test cases and note any issues that may occur with the input (i.e., ranges of numbers accepted, etc). Include comments. Write a program to check whether input alphabet is vowel or not using if-else and switch statement. Include test cases and note any issues that may occur with the input (i.e., ranges of numbers accepted, etc), Include comments