Uniform Resource Identifiers (or URIs) are strings like http://icpc.baylor.edu/icpc/, mailto:foo@bar.org, ftp://127.0.0.1/pub/linux, or even just readme.txt that are used to identify a resource, usually on the Internet or a local computer. Certain characters are reserved within URIs, and if a reserved character is part of an identifier then it must be percent-encoded by replacing it with a percent sign followed by two hexadecimal digits representing the ASCII code of the character. A table of seven reserved characters and their encodings is shown below. Your job is to write a program that can percent-encode a string of characters.
Character Encoding
" " (space) %20
"!" (exclamation point) %21
"$" (dollar sign) %24
"%" (percent sign) %25
"(" (left parenthesis) %28
")" (right parenthesis) %29
"*" (asterisk) %2a