Write the main method of a C program to read a 4-digit integer from the user, validate the user input and output the highest and the lowest digit in the 4-digit
integer.
Given below are some examples.
Example 1:
Enter a 4 digit number:14
Output: There are 2 digits. Please enter a 4 digit number
Example 2:
Enter a 4 digit number: 1453
Output: Highest digit: 5 Lowest digit: 1
Example 3:
Enter a 4 digit number: 14582
Output: There are 5 digits. Please enter a 4 digit number​