Reverse a Four-Digit Number and Test for a Palindrome

Easy

Read a four-digit integer, reverse its digits with a loop, and print two lines: 1221 reversed is 1221 followed by 1221 is a palindrome, or 1234 reversed is 4321 followed by 1234 is not a palindrome. The reversal builds a number with reversed = reversed * 10 + n % 10 while peeling n with / 10, so a number ending in zeros reverses to a shorter number: 1200 reversed is 21. If the input is not between 1000 and 9999, print not a four-digit number and return 1. If it cannot be read, print invalid input and return 1.

Success Criteria

Your code must pass 8 test case(s) to complete this exercise. 3 hint(s) are available if you need help.

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