Write a function, ReverseDigit, that takes an integer as a parameter and returns the number with its digits reversed. For example, the value of ReverseDigit$(1234)$ is $4321$; the value of ReverseDigit$(5600)$ is $65$ ; the value of ReverseDigit$(7008)$ is $8007$ ; and the value of ReverseDigit$(-532)$ is $-235.$ Then, call the function from the main function to demonstrate correctness.

Sample Input$/$Output:

Enter an integer: $609$

The number with the digits reversed is: $906$

Enter an integer: $-1029$

The number with the digits reversed is: $-9201$

Enter an integer: $-900$

The number with the digits reversed is: $-9$