Do-while code for long integer input

Question

It is mentioned in the problem:

American Express uses 15-digit numbers, MasterCard uses 16-digit numbers, and Visa uses 13- and 16-digit numbers.

So with get_long, I perhaps need to restrict input integers by user from 13 to 16 digits.The objective is met for smaller integers such as between 10 and 99.

#include <stdio.h>
#include <cs50.h>
int main(void)
{
int input;
do
    {
      input = get_long("enter");
    }
 while (input<10 || input>99);  

}

Seeking help for ways I can restrict input of integers from 13 to 16 digit numbers. While I can accept input from 10 to 99, not working when instead of 10, replaced with 1000000000000 and 99 replaced with 9999999999999999.

Okay after replacing int with long, indeed I could accept input from 13 to 16 digit numbers.

#include <stdio.h>
#include <cs50.h>
int main(void)
{
long input;
do
    {
      input = get_long("enter");
    }
while (input<1000000000000 || input>9999999999999999); 

}

Answer 1

Hold that thought! If you restrict the input as with a do-while loop, program will continue prompting for the number until it is in the desired range. How will program be able to print correct output as per example:

$ ./credit
Number: 6176292929
INVALID

The problem in the code with the "big numbers" is because input is declared as int, not long. It will not compile on CS50 IDE using make.