// Implements a regex pattern to validate IPv4 addresses. // Ensures the address contains four octets separated by dots. // Each octet is restricted to values between 0 and 255. // Designed according ...

1. Convert both strings to lowercase to make comparison case-insensitive. 2. Check if lengths are equal. 3. Use a frequency array of size 26 (for letters a–z). 4. Increment count for characters in ...