AP Computer Science A Free Response Practice Using the String Class

AP CSA Practice Free Response Question 1

A company needs to format words for display on a website. The rules for formatting are:

• If a word contains more than one occurrence of any vowel ('a', 'e', 'i', 'o', 'u', case sensitive), replace each occurrence after the first with an asterisk (*).
• Trim any white spaces from the beginning and end of the string.
• If the resulting word does not ends with a vowel, append an exclamation mark (!) to the end.

Part a. Write the method formatWord that takes a String parameter word and returns the formatted string as per the rules above.

Examples:

Input	Output
"eager"	"eag*r!"
" outcome "	"outc*me"
"apple"	"apple"
"ChatBot"	"ChatBot!"

String Tutorial

AP CSA Practice Free Response Question 2

Write a class SentenceAnalyzer that analyzes a sentence (a String consisting of words separated by single spaces, with no punctuation). The class has the following methods:

• public static int countWord(String sentence, String word) - to be answered in part a.
• public static String swapFirstLast(String sentence) - to be answered in part b.

Part a: countWord Method

Write a static method countWord that takes two parameters: a String sentence and a String word. The method returns the number of times word appears in the sentence. Two words will not match if there are case discrepancies.

Example:

• countWord("java is fun and java is powerful", "java") returns 2
• countWord("Test test TEST", "test") returns 1

String Tutorial

Part b: swapFirstLast Method

Write a static method swapFirstLast that takes a String sentence and returns a new String in which the first and last words have been swapped. Spaces between words must be preserved, and words are separated by a single space. If there is only one word, return the original sentence.

Examples:

• swapFirstLast("coding is creative") returns "creative is coding"
• swapFirstLast("hello") returns "hello"

String Tutorial