Programming Assignment 2: Recursion Exercises

This program is to be submitted via Blackboard by 10:00 p.m. Monday Feb. 12; I'm making the date late just to allow you to schedule your time.  It should in fact take you only a few hours tops, and the next assignment will be due a few days later and will be much longer.  This assignment will count for less than a full programming assignment. 
Write a class called recursiveUtilities with the following public static methods:

1. A recursive method called minArray that finds the minimum value in an array of int values without using any loops. Input: one array of ints.  Return type: int .  (Based on text C-3.15)

2. A recursive method called isPalindrome that takes a character String and returns a boolean telling whether the input string is a palindrome. (Based on text C-3.19)

3. A recursive method called reverse that takes a character String and returns a String that is the reverse of the original input. (Based on text C-3.18)
Note that in some or all of these cases the public static method may simply be a short wrapper that calls another method that is recursive but takes a different number of parameters.





public class recursiveUtilities {
	public static void main(String[] args) {
		int[] TestArray = {30, 8, 31, 400, 3, 630, 70, 4, 7, 20};
		recursiveUtilities h = new recursiveUtilities();
	    //int smallest = h.minArray(TestArray, Integer.MAX_VALUE, 0);
	   // System.out.println(smallest);
		char[] palindromeCheck = {'a', 'm', 'o', 'm', 'a'};
		String[] charString = {"Testing"};
		//boolean check = h.
		System.out.println("Reverse this: " + charString + swap0rama(charString, 0, charString.length-1));
		System.out.println("isPalindrome? . . . " + isPalindrome(palindromeCheck, 0, palindromeCheck.length-1));
	}

	public static int minArray(int[] array, int currSmallest, int stopIndex){ //left to right
		int localCurrSmallest = Integer.MAX_VALUE;
	
		if (stopIndex == array.length-1){  //if at end of array, done
			return array[stopIndex];
	    }
	    else{
	    	if (array[stopIndex] <  minArray(array, currSmallest, stopIndex+1)){
	    		localCurrSmallest = array[stopIndex];
            }
            else{
	            localCurrSmallest = minArray(array, currSmallest, stopIndex+1);
	            }
	    }
		return localCurrSmallest;
	}
	
	public static boolean isPalindrome(char[] array, int startIndex, int endIndex){
		
		if (array[startIndex]==array[endIndex] && endIndex == 1)
			return true;		
		if (array[startIndex]!=array[endIndex] || endIndex <= 1){
			System.out.println("false.!!.");
			return false;
		}
		else{		
			return isPalindrome(array, startIndex+1, endIndex-1);			
			}
	} 
	public static String swap0rama(String StringArray, int startIndex, int endIndex){
		//base case: end is zero, thus all was swapped
		if (endIndex == 0){
			return backWard;
		}
		if (endIndex > 0){ //if the end isn't reached, copy the value
			String backWard;
			backWard.concat(StringArray.valueOf(endIndex));
		}
		else
		return swap0rama(StringArray, startIndex+1, endIndex-1);
	}
}