Permutations of Symbols Within a String
This program computes the EXACT number of unique permutations, completely different linear
rearrangements, that can be created from a string of symbols or alpha-numeric text characters.

Any symbol character repetitions are also taken properly into account.

Enter A String Of Up To 80 Keyboard Symbols Or Alpha-Numeric Characters (ALL letters ARE case sensitive).

There should be no blank spaces in the string, however another character
could be used to represent spaces, such as the underscore character ( _ ).