Question

JAVA

package stringPractice1068;

public class SomePracticeStringMethods {
/* returns true if c is a punctuation mark or false otherwise
*
* Punctuation mark is defined as:
* apostrophe '
* comma ,
* period .
* semicolon ;
* colon :
* exclamation point !
* question mark ?
*
* (You don't have to worry about any others)
*/
public static boolean isPunct(char c) {
   /* placeholder just so that the function
   * compiles. fill in your implementation here.
   *
   * there is a similar placeholder
   * for each of the remaining functions */
   return true;
}
  
/*
* returns the index of the first punctuation mark in s or
* -1 if s contains no punctuation marks
*/
public static int indexOfFirstPunct(String s) {
   return -1;
}

/*
* returns the index of the first occurrence of a punctuation mark in s starting
* from index startPosition or -1 if there are none at index
* startPosition or later. Notice that this method has the same name as the
* previous one, but that it takes a different number of arguments. This is
* perfectly legal in Java. It's called "method overloading"
*/
public static int indexOfFirstPunct(String s, int startPosition) {
   return -1;
}

/*
* returns the index of the last occurrence of a punctuation mark in s or -1 if s
* contains none
*/
public static int indexOfLastPunct(String s) {
   return -1;
}

/*
* returns s in reverse. For example, if s is "Apple", the method returns the
* String "elppA"
*/

Answer 1

package stringPractice1068;

public class SomePracticeStringMethods {

    public static boolean isPunct(char c) {
        return c == '\'' || c == ',' || c == '.' || c == ';' || c == ':' || c == '!' || c == '?';
    }

    public static int indexOfFirstPunct(String s) {
        return indexOfFirstPunct(s, 0);
    }

    public static int indexOfFirstPunct(String s, int startPosition) {
        for(int i = startPosition; i < s.length(); ++i) {
            if(isPunct(s.charAt(i))) {
                return i;
            }
        }
        return -1;
    }

    public static int indexOfLastPunct(String s) {
        return indexOfLastPunct(s, s.length()-1);
    }

    public static int indexOfLastPunct(String s, int endPosition) {
        for(int i = endPosition; i >= 0; --i) {
            if(isPunct(s.charAt(i))) {
                return i;
            }
        }
        return -1;
    }

}