Write a program rot13 that encodes a string using the ROT-13 encoding. ROT-13, or rotate 13 is a simple cipher that maps each letter to a letter thirteen places later or earlier in the alphabet. Thus, A (letter 1) maps to N (letter 14), and vice versa. rot13 takes one argument, a string, and prints the result of encoding that string in ROT-13

Usage

$ ./rot13 Uryyb

Hello

$ ./rot13 Awesome Power!

Njrfbzr Cbjre!

Use argc and argv for inputs