Given the following informal specification: The program prompts the user for a positive integer in the range 1 to 20 and then for a string of characters of that length. The program then prompts for a...

Given the following informal specification: The program prompts the user for a positive integer in the range 1 to 20 and then for a string of characters of that length. The program then prompts for a character and returns the position in the string at which the character was first found or a message indicating that the character was not present in the string. The user has the option to search for more characters. Produce black box-based test cases using both boundary value analysis and equivalence classes techniques.