The last digit d11 is a checksum, which is calculated from the other digits using the following formula:

10 - (d1 + 3d2 + d3 + 3d4 + d5 + 3d6 + d7 + 3d8 + d9 + 3d10)%10. If the checksum is 10, replace it with 0.

1. Write a function named readString that takes only an array of character as parameter named data, reads a string of size 11 from the user, and sore it the array data. The function should ask the user to enter a proper string of until the user enters a string of size 11

2. Write a function named checkSum that takes only one input parameters str of type char* (null-terminated C strings of characters) and calculates and returns the check sum from the first 10 digits

3. Write the main function that

• Prints your full name and Student ID
• Define a proper variable to store a c-string
• Properly call the function readString to read a n 11-digit national ID
• displays valid national ID if the digit 11 equals the checksum calculated in part2 or invalid otherwise

4. Add your name, your University ID number and section number as a comment at the beginning of this program.