Usage: ./cipher2 [option] [url]
Options: -s Shorten a long URL using TinyURL API -u Unshorten a short URL to reveal its target -h Show this help message
Examples: ./cipher2 -s https://example.com ./cipher2 -u https://tinyurl.com/abc123
Notes:
- Requires internet connectivity and libcurl.
- Caller must free() strings returned by -s and -u options.
- Compile with: gcc -std=c99 -o ./cipher2 ./cipher2.c -lcurl